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Organic Electronics for Electrochromic Materials and Devices
Organic Electronics for Electrochromic
Materials and Devices
Hong Meng
Author All books published by Wiley-VCH
are carefully produced. Nevertheless,
Prof. Hong Meng authors, editors, and publisher do not
Peking University warrant the information contained in
Shenzhen Graduate School these books, including this book, to
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© 2021 WILEY-VCH GmbH,

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All rights reserved (including those of

translation into other languages). No
part of this book may be reproduced in
any form – by photoprinting,
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transmitted or translated into a
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permission from the publishers.
Registered names, trademarks, etc.
used in this book, even when not
specifically marked as such, are not to
be considered unprotected by law.
Print ISBN: 978-3-527-34871-8

ePDF ISBN: 978-3-527-83061-9
ePub ISBN: 978-3-527-83062-6
oBook ISBN: 978-3-527-83063-3
Typesetting SPi Global, Chennai, India

Printing and Binding
Printed on acid-free paper
10 9 8 7 6 5 4 3 2 1
v
Contents
Preface xiii
About the Author xiv
1 Introduction 1
1.1 General Introduction 1
1.2 The History of Electrochromic Materials 3
1.3 The Key Parameters of Electrochromism 5
1.3.1 Electrochromic Contrast 5
1.3.2 Switching Time 8
1.3.3 Coloration Efficiency 9
1.3.4 Optical Memory 11
1.3.5 Stability 12
1.4 Conclusion 14
References 14
2 Advances in Polymer Electrolytes for Electrochromic

Applications 17
2.1 Introduction 17
2.2 Requirements of Polymer Electrolytes in Electrochromic
Applications 18
2.3 Types of Polymer Electrolytes 20
2.3.1 Gel Polymer Electrolytes (GPEs) 20
2.3.1.1 PEO-/PEG-Based Electrolytes 21
2.3.1.2 PMMA-Based Polymer Electrolytes 21
2.3.1.3 PVDF-Based Polymer Electrolytes 22
2.3.2 Self-Healing Polymer Electrolytes 24
2.3.3 Cross-Linking Polymer Electrolytes (CPEs) 26
2.3.4 Ceramic Polymer Electrolytes 27
2.3.5 Ionic Liquid Polymer Electrolytes 30
2.3.6 Gelatin-Based Polymer Electrolytes 32
2.4 Conclusion and Future Outlook 33
References 40
vi Contents
3 Electrochromic Small Molecules 49

3.1 Background of Small Molecule Electrochromic 49
3.2 Technology Development of Small Molecule Electrochromic
Materials 50
3.3 Violene–Cyanine Hybrids (AIE PL OEC) 50
3.4 Terephthalate Derivatives (Multicolor OEC) 56
3.4.1 Conclusion 63
3.5 Isophthalate Derivatives 64
3.5.1 Conclusion 79
3.6 Methyl Ketone Derivatives 79
3.6.1 Conclusion 84
3.7 Diphenylacetylenes 84
3.8 Fluoran Dye Derivatives 85
3.9 PH-Responsive Molecule Derivatives 92
3.10 TPA Dye Derivatives 95
3.11 Hydrocarbon Derivatives-NIR-OEC 99
3.12 Conclusions and Perspective 101
References 101
4 Viologen OEC 105

4.1 The Introduction of OEC and Viologen 105
4.1.1 General Introduction 105
4.1.2 Research History of Viologen 105
4.1.2.1 First Stage (1930s–1970s) 107
4.1.2.2 Second Stage (1970s–2000s) 107
4.1.2.3 Third Stage (2000s–2010s) 107
4.1.2.4 Fourth Stage (2010s–Present) 108
4.1.3 Electrochromism and Electrochemistry of Viologens and Their
Device 109
4.2 Different Structures of Viologen-Based Electrochromic Materials 110
4.2.1 Synthesis of Viologens 110
4.2.1.1 Direct Substitution Reaction 110
4.2.1.2 Zincke Reaction 110
4.2.1.3 Methods for Synthesizing Bipyridine 110
4.2.2 The 1,1′ -Substituted Viologen 111
4.2.2.1 Simple Alkyl 111
4.2.2.2 Acid Group 111
4.2.2.3 Ester and Nitrogen Heterocycle 112
4.2.2.4 Asymmetric Substitution 113
4.2.3 Conjugate Ring System Expansion 113
4.2.3.1 Thiazolothiazole (TTz) Unit 113
4.2.3.2 Perylenediimide (PDI) Unit 115
4.2.3.3 PBEDOTPh 115
4.2.3.4 Heteroatoms Bridged 115
4.2.3.5 Bithiophene Bridged 118
Contents vii
4.2.4 Viologen-Based Polymer 119

4.2.4.1 Viologen in the Side Chain 120
4.2.4.2 Viologen in the Main Chain 122
4.3 Viologen Electrochromic Device 124
4.3.1 Device Structure 124
4.3.1.1 Five-Layer Classic Structure 124
4.3.1.2 Simple Sandwich Structure 125
4.3.1.3 Cathodic Anode Separation Structure 125
4.3.1.4 Reflective Device Structure 126
4.3.2 Electrolyte 126
4.3.3 Redox Mediator 126
4.3.4 Conductive Medium 128
4.3.5 Problems with Viologen Compound 128
4.3.5.1 Dimerization 128
4.3.5.2 Aggregation and Solubility 131
4.3.5.3 Response Time 131
4.3.5.4 Driving Voltage 131
4.3.5.5 Conclusion 131
4.3.6 Examples of Viologen-Based ECD 132
4.4 Companies Operating in the Field of Viologen Electrochromism 132
4.4.1 Gentex 132
4.4.2 Essilor 134
4.4.3 Haoruo 134
4.5 Conclusion 134
References 135
5 Metallohexacyanates 143
5.1 Background 143
5.2 Technology Development of PB 144
5.3 Crystal Structure 144
5.4 Electrochromic Mechanism 145
5.5 Synthesis 147
5.6 Electrochromic Devices (ECDs) 150
5.7 Nanocomposites 154
5.8 PB Analogs 160
5.9 Multifunctional Applications 170
References 175
6 Electrochromic Conjugated Polymers (ECPs) 183

6.1 Introduction 183
6.1.1 Common Categories and Operation Mechanism 183
6.1.2 Synthetic Methods 186
6.2 Thiophene-Based Conjugated Electrochromic Polymers 190
6.2.1 Introduction 190
6.2.2 Color-Tuning Strategies for Thiophene-Based Polymers 191
viii Contents
6.2.2.1 Steric Effects 192

6.2.2.2 Substituent and Electronic Effects 193
6.2.3 Typical Colored Polymers 195
6.2.3.1 Yellow and Orange 196
6.2.3.2 Red 198
6.2.3.3 Magenta and Purple 199
6.2.3.4 Black 202
6.2.3.5 Multicolored 203
6.2.3.6 Anodically Coloring Polymers 205
6.2.4 Water- or “Green Solvents”-Soluble ECPs 208
6.3 Polypyrroles-Based Conjugated Electrochromic Polymers 216
6.3.2 Electrochromic Properties of Polypyrroles (PPy) 218
6.3.3 Tuning of Electrochromic Properties of Polypyrrole (PPy) 218
6.3.3.1 Structural Modification 218
6.3.3.2 3- and 3,4-Substituted Polypyrroles 235
6.3.3.3 Donor–Acceptor Approach 236
6.3.3.4 Terarylene Systems 237
6.4 Polycarbazole-Based Conjugated Electrochromic Polymers 237
6.4.2 Electrochromic Properties of Polycarbazoles (PCARB) 238
6.4.3 Electrochromic Properties of Polycarbazoles Derivatives 238
6.4.3.1 Linear Polycarbazole Derivatives 241
6.4.3.2 Cross-Linked Polycarbazoles Derivatives 249
References 260
7 TA-Based Electrochromic Polyimides and Polyamides 269

7.1.1 Aromatic Polyimides and Polyamides 269
7.1.2 Triarylamine-Based Aromatic Polymers 270
7.1.3 Electrochemical and Electrochromic Behaviors of MV Triarylamine
Systems 272
7.2 Development of TA-Based Electrochromic Polyimides and
Polyamides 272
7.2.1 Side Group Engineering 276
7.2.1.1 Introduction of Protecting Groups 276
7.2.1.2 Introduction of Electroactive Groups to Achieve Color Tuning of EC
Material 277
7.2.1.3 Introduction of Side Groups to Achieve Electrofluorochromic
Materials 278
7.2.1.4 Introduction of Other Functional Side Groups to Achieve Multiple
Functions EC Material 281
7.2.2 Backbone Modulation 283
7.2.2.1 Extending the Polymer Backbone by Introducing More Electroactive
Groups 283
Contents ix
7.2.2.2 Introduction of Amide Linkage into Polyimide Backbone 285

7.2.2.3 Introduction of Ether Linkage into PIs/PAs Backbone 285
7.2.2.4 Introduction of Alicyclic Structures into PIs/PAs Backbone 288
7.3 Conclusions 290
References 290
8 Metallo-Supermolecular Polymers 295

8.2 Single Metallic System 296
8.2.1 Fe(II)- and Ru(II)-Based Metallo-Supramolecular Polymers 296
8.2.2 CoII -Based Metallo-Supramolecular Polymers 299
8.2.3 ZnII -Based Metallo-Supramolecular Polymers 301
8.2.4 Cu-Based Metallo-Supramolecular Polymers 305
8.2.5 EuIII -Based Metallo-Supramolecular Polymers 308
8.3 Hetero-Metallic System 311
8.4 The Fabrication Method of Metallopolymer Film 314
8.4.1 Layer-by-Layer Self-Assembly and Dip-Coating Methods 314
8.4.2 Electropolymerized Conducting Metallopolymers 315
8.5 Conclusion 323
References 323
9 Metal-Organic Framework (MOF)- and Covalent Organic

Framework (COF)-Based Electrochromism (EC) 327
9.2 Current Studies in EC MOFs 327
9.2.1 The Organic Linkers in EC MOFs 328
9.2.1.1 NDI-Based Organic Linkers 328
9.2.1.2 Other Organic Linkers 332
9.2.2 The Transport of Electrolyte Ions in EC MOFs 335
9.2.3 Special EC MOFs 338
9.2.3.1 Photochromic and Electrochromic Multi-Responsive MOF 338
9.2.3.2 MOF-Based Double-Sided EC Device and Other Color-Switching
Mechanisms 339
9.2.3.3 EC Base on “Guest@MOF” Composite System 340
9.3 Current Studies in EC COFs 341
9.4 Conclusion and Prospect 348
References 348
10 Nanostructure-Based Electrochromism 353

10.2 Current Studies of Nanostructure in Electrochromism 354
10.2.1 Non-Electrochromic Active Materials as a Template for ECs 354
10.2.1.1 Photonic Crystals as Templates for ECs 354
10.2.1.2 Plasmonic Structures as Templates for ECs 359
x Contents
10.2.2 Nanostructured Electrochromic Materials in ECs 365

10.3 Conclusion and Prospect 369
References 369
11 Organic Electroluminochromic Materials 373

11.2 Conventional Mechanisms of Electroluminochromism 375
11.2.1 Intrinsic Mechanism 375
11.2.2 Electron Transfer (ET) Mechanism 376
11.2.3 Energy Transfer (EnT) Mechanism 376
11.3 Electroluminochromic Performance Parameters 376
11.3.1 Emission Contrast 376
11.3.2 Switching Time 377
11.3.3 Long-Term Stability/Cycle Life 377
11.4 Classical Materials 378
11.4.1 Small Molecules 378
11.4.1.1 Small Molecular Dyads 378
11.4.1.2 Redox-Active Moiety and Luminophores System 380
11.4.1.3 Electroactive Luminophores 382
11.4.2 Transition Metal Complexes 386
11.4.3 Polymers 387
11.4.3.1 Non-Conjugated Polymers 387
11.4.3.2 Conjugated Polymers 396
11.4.4 Nanocomposite Films 407
11.5 Future Perspectives and Conclusion 408
References 408
12 Organic Photoelectrochromic Devices 415

12.2 Structure Design of PECDs 417
12.2.1 Power Supply for PECD 417
12.2.1.1 DSSC-Based PECD 418
12.2.1.2 PSC-Based PECD 423
12.2.1.3 OPV-Based PECD 423
12.2.2 Electrochromic Materials in PECD 425
12.2.2.1 Small Molecule 425
12.2.2.2 Conducting Polymers 427
12.2.2.3 Near-Infrared (NIR) Electrochromic Materials 433
12.2.3 Electrolytes in PECD 435
12.2.4 Substrates in PECD 435
12.3 Future Perspectives and Conclusion 436
References 436
13 Application of OEC Devices 445

13.1 Smart Window 445
Contents xi
13.1.1 The Structure and Working Mechanism of Smart Windows 445

13.1.2 The Materials for Electrochromic Windows 446
13.1.3 Prospects 450
13.2 Dimmable Rearview Mirror 450
13.3 Sensors 451
13.3.1 Application of Electrochromic Sensors on Food Preservation 451
13.3.2 Application in Bio-Sensing 454
13.4 The Application of Electrochromic Device in Display 460
13.5 Other Applications of OEC 462
References 469
14 Commercialized OEC Materials and Related Analysis of

Company Patents 471
14.1 General Introduction 471
14.2 Gentex Corporation 471
14.3 Ricoh Company, Ltd. 475
14.4 Canon Inc. 476
14.5 BOE Technology Group Co., Ltd. and OPPO Guangdong Mobile
Communications Co., Ltd. 477
14.6 Other Important Enterprises 481
14.6.1 Ninbo Ninuo Electronic Technology Co., Ltd. 481
14.6.2 Ambilight Inc. 483
14.6.3 Furcifer Inc. 483
14.6.4 Changzhou Spectrum New Material Co. Ltd. 484
14.7 Conclusion 485
References 485
15 Main Challenges for the Commercialization of OEC 491

15.2 The Long-Term Stability of OEC Materials 491
15.3 The Mechanical Stability of OEC Devices (Encapsulation
Technology) 495
15.4 Large-Area Process Technology: Spray Coating and Roll-to-Roll
Processes 498
15.4.1 Inkjet Printing 498
15.4.2 Spray Coating 500
15.4.3 Slot-Die Coating 500
15.4.4 Screen Printing 501
15.5 Conclusions and Perspective 501
References 502
Index 505
xiii
Preface
In recent years, with the development of artificial intelligence, more and more
industries strive to be “smart.” As a new generation of display technology, organic
electrochromic (OEC) devices offer numerous advantages such as flexibility, full
colors, wide origins of materials, fast switching time, low driving voltage, and
simple configuration. In addition, these devices possess “smart” characteristics of
multi-stimulation and multi-response. Therefore, the OEC industry is emerging as
a potential display competitor in the field of electronic information.
This book covers major topics related to the phenomenon of electrochromism,
including the history of organic electrochromism, fundamental principles, different
types of electrochromic materials, development of device structures, multifunctional
devices, their characterizations and applications, and future prospects of OEC tech-
nology. It also spotlights recent research progress reported by academic institutes
and enterprises, and discusses the existing challenges in further development of this
area.
This book provides a comprehensive review of OEC materials and devices, and
can be used as a teaching reference for undergraduate and graduate students as well
as teachers in the fields of organic chemistry and polymer science etc. Also, this
book can be adopted as a comprehensive reference for researchers engaged in the
development of OEC technology enterprise in the field of electrochromism.
Shenzhen, PR China Hong Meng

11 November 2020
xiv
About the Author
Prof. Dr. Hong Meng obtained his BS in Chemistry at

Sichuan University in 1988 and MS degree in Organic
Chemistry from Peking University in 1995. He then studied
Polymer Science and Engineering and acquired his second
MS degree from the National University of Singapore in
1997. After working at the Institute of Materials Science
and Engineering (IMRE) in Singapore for two years, he
went to the United States in 1999 and completed his PhD
under the supervision of Prof. Fred Wudl at the University
of California, Los Angeles (UCLA), in 2002. Prof. Dr. Meng worked as a research
consultant at Bell Labs, Lucent Technologies, with Dr. Zhenan Bao for one year. He
then joined DuPont Experimental Station, Central Research and Development, as a
senior research chemist in 2002. In 2012, he moved back to China and worked as the
CEO of a laser printing industry at Leputai Technology Company. In 2014, he joined
the School of Advanced Materials at Peking University, Shenzhen as a chair pro-
fessor. He has been engaged in the research and development of solid-state organic
synthesis, organic semiconductor device engineering, organic electronics, and other
relevant fields, especially organic light-emitting diodes, organic electrochromics,
organic thin-film transistors, organic conductive polymers, and nanotechnology. He
has published more than 200 articles in internationally renowned journals, partici-
pated in the writing of three book chapters and co-edited two books in the field of
organic optoelectronic technology. He has obtained more than 150 patents for inven-
tions in the United States and China, among which, several patented products have
been commercialized.
1
Introduction
1.1 General Introduction

Electrochromism is the phenomenon that describes the optical (absorbance/
transmittance/reflectance) change in material via a redox process induced by an
external voltage or current [1]. Usually the electrochromic (EC) materials exhibit
color change between a colored state and colorless state or between two colors,
even multicolor. In nature, its origin is from the change of occupation number of
material’s internal electronic states. As the core of EC technology, the EC materials
have built up many categories during decades of development, for example, accord-
ing to the coloration type, it could be classified as anodically coloring materials
(coloration upon oxidation) or cathodically coloring materials (coloration upon
reduction) [2]. Based on the light absorption region in the solar radiation, which
consists of these three parts: ultraviolet (UV), visible (Vis), and near-infrared
radiation (NIR) lights (Figure 1.1), it could be divided into visible EC materials
(wavelength: 380–780 nm), which can be seen by the human eye and therefore
are suitable for smart window and indicator applications, and NIR EC materials
(wavelength: 780–2500 nm), which have great potential for thermal regulation
technologies and even in national defense-related applications [3]. And on the
basis of materials species, there are mainly inorganic, organic, and hybrid EC mate-
rials [4, 5] (https://commons.wikimedia.org/wiki/File:Solar_spectrum_en.svg).
Inorganic EC materials are transition metal oxides (TMOs) (WO3 , NiO, TiO2 , and
Prussian Blue [PB]), organic EC materials including small molecules (e.g. viologen),
conjugated polymers (e.g. poly(pyrrole), poly(thiophene), and poly(carbazole)) and
aromatic polymers (e.g. polyimides [PIs] and polyamides [PAs]), organic–inorganic
hybrid materials referring to metallo-supermolecular polymers, and metal–organic
framework (MOF). Among them, inorganic materials exhibit excellent long-term
stability compared with organic ones; however, considering the structure variety,
flexibility, and low-cost solution processability, organic EC materials are superior
to inorganic materials. The organic–inorganic hybrid materials are designed to
combine advantages of both organic and inorganic materials.
EC materials exhibit color changes during the redox process; therefore the
electrochromic devices (ECDs) generally consist of three elements: electrodes, EC
materials, and electrolyte solution. The electrodes offer a constant supply of electric
Organic Electronics for Electrochromic Materials and Devices, First Edition. Hong Meng.
© 2021 WILEY-VCH GmbH. Published 2021 by WILEY-VCH GmbH.
2 1 Introduction
2.5
UV Visible Infrared
2
Irradiance W/(m2 nm)
Sunlight without atmospheric absorption
1.5
5778 K blackbody
1
Sunlight at sea level
H2 O
Atmospheric
0.5 H2O
absorption bands
O2
H2O CO
O3 H2O 2 H2O
0
250 500 750 1000 1250 1500 1750 2000 2250 2500
Wavelength (nm)
Figure 1.1 Solar irradiance spectrum above atmosphere and at the surface of the Earth.
Source: Nick84: https://commons.wikimedia.org/wiki/File:Solar_spectrum_en.svg, Licensed
under CC BY-SA 3.0.
Figure 1.2 The scheme of three types of electrochromic devices.
current, and ions are conducted by the electrolyte solution. Then the EC materials
undergo electrochemical oxidation and/or reduction, which results in changes in
the optical bandgap and colors. As shown in Figure 1.2, a typical ECD has five layers:
two transparent conducting oxide (TCO) layers, EC layer, ion-conducting layer
(electrolyte solution), ion storage layer. Particularly, the ion storage layer acts as the
“counter electrode” to store ions and keep electric charge balance. And according to
the exact state of EC materials, there are three types of ECD: film type (I), solution
type (II), and hybrid type (III). The Type I ECD is the most common; many kinds of
EC materials are suitable for this type including TMOs, conjugated/non-conjugated
polymers, metallo-supermolecular polymers, and MOF/covalent organic frame-
work (COF) materials, which using spin-coating, spray-coating, and dip-coating
processes to form uniform films; these films won’t dissolute in electrolyte solutions.
Type II ECD requires that the EC materials have good solubility in electrolyte
1.2 The History of Electrochromic Materials 3
solutions. Therefore many organic small molecules such as viologen, terephthalate

derivatives, and isophthalate derivatives are appropriate for this type of device.
Meanwhile the fabrication method for this type of device is the most simple one.
It just needs to dissolve the electrolyte and EC material in a specific solvent and
inject into the prepared conducting cell. Type III ECD uses film-type EC materials
as working electrode and solution-type EC materials as ion storage layer.
1.2 The History of Electrochromic Materials
The word “electrochromism” was invented by John R. Platt in 1960 [6], in analogy
to “thermochromism” and “photochromism.” However, the EC phenomenon could
be traced to the nineteenth century, as early as 1815. Berzelius observed the color
change of pure tungsten trioxide (WO3 ) during the reduction when warmed under
a flow of dry hydrogen gas. Then from 1913 to 1957, some patents described the
earliest form of ECD based on WO3 [7, 8]. Therefore the origins of electrochromism
are the nineteenth and twentieth centuries. After then, electrochromism technology
began to undergo rapid development, especially the exploration of many classes of
EC materials. As showed in the technology roadmap (Figure 1.3), we summarized
several generations of EC materials during long-term development.
The first-generation EC material is TMOs (e.g. WO3 , NiO, and PB). Among them,
WO3 plays an important role in the electrochromism field; as the first founded EC
material, it has already realized commercialization in smart windows application.
PB was discovered as a dye by Diesbach in 1704, and then the electrochemical behav-
ior and EC performance of PB was firstly reported by Neff at 1978 [9]. Benefitted
from the structure stability and reversible redox process of those inorganic TMOs,
the electrochromism based on the thin-film TMOs are widely investigated, including
n
S n N n O n N
H H
Poly(thiophene) Poly(pyrrole) Poly(furan) Poly(anlline) N N
n n
n N M N
N n
N N
N
H
Poly(carbazole) Poly(fluorene) Poly(triphenylamine) M = Fe, Co, Ru, Cu, Zn, Eu
Transition metal oxides (TMOs) Conjugated polymers (CPs) Metallo-supermolecular polymers

The first generation The third generation The fifth generation
Rigid Flexible Stretchable Wearable
1913–1957 1960 1970 1980 2000 2010
The second generation The fourth generation The sixth generation
Organic small molecule Triarylamine-based aromatic polymers MOFs/COFs
O O
R
N N
+ + n
N N – RO OR N
–
Br Br O O
O O
Viologen Terephthalate derivatives COF3PA-TT
H HO O
N N C C
n
N
Figure 1.3 The roadmap of EC materials development.

4 1 Introduction
the development of new TMOs materials, introduction of new nanostructures, and

different element doping.
Following the first-generation TMO EC materials, organic small molecule EC
materials have emerged since 1970. Among them, viologen as the most represen-
tative small molecule was first discovered by Michaelis and Hill in 1932 [10], and
because of the violet on the reduction, these 1,1′ -disubstituted-4,4′ -bipyridine com-
pounds were named “viologen.” Then in 1973, Shoot made a new flat alphanumeric
display using heptyl viologen; this can be regarded as the beginning of the use of
viologen for electrochromism [11]. After a century’s development, viologen already
has been successfully commercialized. Besides the viologen, other small molecules
EC materials such as terephthalate derivatives, isophthalate derivatives, methyl
ketone derivatives, and some dye molecules have also attracted much attentions
from scientists due to their simple structure and low cost.
The third-generation EC materials are conjugated polymers. In 1983, Francis
Garnier and coworkers firstly characterized the EC properties of a series of
five-membered heterocyclic polymers including poly(pyrrole), poly(thiophene),
poly(3-methylthiophene), poly(3,4-dimethylthiophene), and poly(2,2′ -dithiophene).
Since then, conjugated polymers were given rise to the rapid emerge as a new class
of electrochromism [12]. Five years later, Berthold Schreck observed the elec-
trochromism phenomenon of poly(carbazole), which showed a color change
from pale yellowish to green together with the conductivity enhancement [13].
To date, the conjugated polymer EC system has been well developed, from bet-
ter understandings on mechanisms to completed color pallette with soluble or
electro-deposited polymers, and even full-color display samples or roll-to-roll
fabricated flexible devices.
Later, in early 2000, triarylamine (TA)-based aromatic polymers especially the
PIs and PAs have drawn considerable attention from the research community
as the fourth-generation EC materials. The correlation between electrochemical
properties and chemical structures of different aromatic PIs was firstly described
in 1990. Ten years later, Zhiyuan Wang and coworkers [14] reported the first EC
behavior of poly(ether naphthalimide)s, which showed stepwise coloration process,
from colorless to red and to dark blue corresponding to the neutral, radical anion,
and dianion species, respectively. However, due to the high rigidity of the PIs/PAs
backbone and strong intermolecular interactions, the poor processability limited the
development of PIs or PAs EC materials. Therefore the TA groups were introduced
to the PIs/PAs backbone to improve the solubility of aromatic polymers. The first
TA-based polyamide PA was synthesized in 1990 [15], and the first aromatic poly-
imides integrating interesting EC properties containing TA groups were disclosed
in 2005 [16]. Since then, Liou, Hsiao and, other groups have developed numerous
TA-based EC PIs/PAs. Most of the PIs/PAs were solution processible and thermally
stable with excellent adhesion with indium tin oxide-coated glass electrode and had
good electrochemical stability. Now the TPA-based PIs/PAs are considered as great
anodic EC materials due to proper oxidation potentials, electrochemical stability,
and thin-film formability.
Benefiting from the bloom and revolution of organic polymers, metallo-super-

molecular polymers were developed by incorporating metal centers into synthetic
polymer chains, as the fifth-generation EC materials. The first metal-containing
polymer, poly(vinyl-ferrocene), was reported in as early as 1955 [17]. However,
due to the insolubility of those macromolecules and the limitation of characteristic
technologies in the early years, the metallo-supermolecular polymers haven’t been
rapidly developed until the mid-1990s [18]. Since then, metallo-supermolecular
polymers began to be widely explored in EC field with the advantages of beneficial
properties of both organic and inorganic materials. Especially, because the transi-
tion metal complexes often exhibit well-defined redox events and intense charge
transfer transitions in the NIR region, metallo-supermolecular polymers often show
potentials in NIR EC application.
More recently, with the active researches on the crystalline and porous MOFs
and COFs, the sixth-generation MOFs/COFs EC materials have emerged. In 2013,
the first EC properties of MOFs using naphthalene diimide (NDI) as organic linker
were reported by Professor M. Dinca’s group [19]. And the first COFs EC material
using the TPA as building block was revealed by Yuwu Zhong and Dong Wang
and coworkers in 2019 [20]. All in all, some essential features of MOFs/COFs give
them advantages in EC, including designable and precise molecular structure,
simple self-assembly synthesis, and porous structure that facilitate the electrolyte
ions transport. However, these new EC materials haven’t been fully revealed; many
efforts should be taken to improve the device performance of MOFs/COFs-based
electrochromism.
1.3 The Key Parameters of Electrochromism

In order to elucidate the EC properties of EC materials, in situ UV–Vis–NIR spec-
troelectrochemistry (SEC) measurements were performed on a spectrophotometer,
combining with an electrochemical workstation to apply and control the potential
in the SEC cell. This SEC spectrum dynamically records the absorption change of
EC materials during different applied voltage, which reflects the color change dur-
ing the whole redox process. As an example, the SEC of a black-to-transmissive EC
material is shown in Figure 1.4. Both absorbance model and transmittance model
could be used to carry out the SEC measurement.
1.3.1 Electrochromic Contrast

EC contrast (Δ%T) is measured as the percent transmittance change of the EC
material at a specific wavelength [22] it is a primary parameter for characterizing
the EC materials. It is calculated from the difference of light transmission (TM) in
the bleached and colored state TMb and TMc at the specified wavelength. And the
transmittance values are generally recorded upon the application of square-wave
potential steps to the electroactive film placed in the beam of a spectrophotometer.
Each color has a characteristic wavelength as shown in Figure 1.5b, such as the
6 1 Introduction
–0.2 V 0V 0.2 V 0.4 V

1.4 0.6 V 0.7 V 0.8 V 0.9 V
1.0 V 1.1 V 1.2 V 1.3 V
1.2 1.4 V
Absorbance (a.u.)
PTTBTTh0.30
1.0
0.8
0.6
0.4
0.2
0.0
400 600 800 1000 1200 1400 1600 1800
Wavelength (nm)
(a)
80
–0.2 V
70 1.4 V
Transmittance (%)
60
Reduction
Oxidation
50
40
30
20
10
400 500 600 700 800
(b) Wavelength (nm)
Figure 1.4 The spectroelectrochemistry (SEC) of a black-to-transmissive EC material. (a)

Absorbance model and (b) transmittance model. Source: Reproduced by permission Li et al.
[21]. © 2018, Royal Society of Chemistry.
wavelength of blue color is ranging from 455 to 490 nm. Therefore, in most cases,
the contrast in the characteristic wavelength is chosen to evaluate the degrees of
color change. Usually the absorption of this characteristic wavelength also reaches
its maximum value (𝜆max ). Moreover, there is evidence that human eyes are most
sensitive to green light with a wavelength of 555 nm [25]. It’s also recommended to
calculate the contrast in 555 nm for comparison in different publications. Specif-
ically, a contrast test example is shown in Figure 1.5a, the TMb and TMc of 𝜆max
425 nm are 1% and 99%, respectively; therefore the Δ%T is calculated as 98%. For
applications such as smart windows, in which the difference between the bleached
and colored states is expected to be the highest, the Δ%T should be higher than
80%. Many inorganic EC materials, organic small molecules, and PEDOT series
polymers, which have a high transmittance in the bleached state, can achieve this
index. Especially, some reported small molecule EC materials even show Δ%T
exceed 95% [23].
–2.2 V, 425 nm 0 425 nm

100
Transmittance (%)
Transmittance (%)
80 20
60 40
98%
40 60
20 80
0 100
0 100 200 300 400 500 600 0 20 40 60 80

(a) Time (s) Time (s)
100 683
555 nm CIE 1978 60 PTTPhBT0.35
Luminous efficiency (lm/W)

Photopic vision PTTThBT0.30
Eye sensitivity function V(λ)
10
–1 100 55
L* 50
10
10–2
45
1 40
10–3
Orange
Yellow
Green
Violet
35
Cyan
Blue
Red
–4
0.1
10 –0.2 0.0 0.2 0.4 0.6 0.8 1.0 1.2
300 400 500 600 700 800
Potential (V)
Wavelength λ (nm)
(b) (c)
Figure 1.5 (a) The electrochromic contrast of a small molecule EC material. Source: Jiang
et al. [23], (b) sensitivity function of the human eye V (𝜆) and luminous efficacy vs
wavelength. Source: Fred Schubert [24]. © 2006, Cambridge University Press. (c) The
change of the lightness values from the neutral to the oxidized states. Source: Li et al. [21].
© 2018, Royal Society of Chemistry.
Meanwhile, for some broad absorption or color-to-colorless EC materials,

measurements on the relative luminance change (Δ%Y ) during an EC switch
are more realistic for exhibiting the overall EC contrast, which conveys more
information on the perception of transmittance to the human eye. As an example,
a luminance change curve during the redox process of black-to-transmissive EC
materials is shown in Figure 1.5c. The lightness L* value (from 0 (black) to 100
(white)) of 37.5 (black state) increases to 60 (bleach state); therefore the Δ%Y is
calculated as 22.5%.
Except for the aforementioned method for electrochemical contrast measure-
ments, a photopically weighted value called photopic contrast was proposed by
Javier Padilla et al. [26]. The photopic contrast also reflects an overall contrast
during the whole visible region, which is more consistent with the real application
condition. It can be calculated using the following equation:
𝜆
∫𝜆 max T(𝜆)S(𝜆)P(𝜆)d𝜆
min
Tphotopic = 𝜆
∫𝜆 max S(𝜆)P(𝜆)d𝜆
min
where T photopic is the photopic transmittance, T(𝜆) is the spectral transmittance of

the device, S(𝜆) is the normalized spectral emittance of a 6000 K blackbody, and P(𝜆)
8 1 Introduction
is the normalized spectral response of the eye. 𝜆min and 𝜆max define the considered
range of wavelengths.
1.3.2 Switching Time

In the context of electrochromism, the switching time (t) can be defined as the time
needed for EC materials to switch from one redox state to the other. It is gener-
ally followed by a square wave potential step method coupled with optical spec-
troscopy. Switching time depends on several parameters, such as the ability of the
electrolyte to conduct ions as well as the ease of intercalation and deintercalation of
ions across the EC active layer, the electrical resistances of electrolytes, and the trans-
parent conducting films. Usually the liquid electrolyte has a lower resistance than
the solid electrolyte; therefore the half device and the liquid electrolyte ECD will
exhibit a rapid switching than solid ECD. Meanwhile, the large area ECD such as the
large smart windows will show a lower switching compared with the small labora-
tory samples due to the larger electrical resistances of transparent conducting films.
However, fast switching is not required in all applications, such as the switchable
window technologies; the obvious color change process will increase the fun of user
experience. Conversely, the sub-second magnitude rapid switching is particularly
desired for display applications.
Usually the switching times are evaluated at the 𝜆max or 555 nm together with
the EC contrast. Therefore there are two kinds of switching time. One is electro-
chemical switching time, as shown in Figure 1.6a, which is the time required for
the current density to change by 90% or 95% between two constant voltages. Mean-
while the switching time of oxidization (toxidization ) and reduction (treduction ) process
can be estimated from this curve. The other is optical switching time (Figure 1.6b),
which defines the time needed for the transmittance to change by 90% or 95%. Cor-
respondingly, the coloration switching time (tcoloration ) and bleaching switching time
(tbleaching ) are recorded in this measurement. It is worth noting that the pulse length
of potential step has influence in transmittance. A shorter potential step will achieve
a smaller contrast, and longer potential will allow EC materials to reach stationary
transmittance value in both coloration and bleaching state. But after a certain length,
continuing increase the pulse length won’t boost the contrast. Therefore the pulse
length that just reached the highest contrast are applied to switching time as well as
contrast tests.
However, the aforementioned method of switching time is an experiential mea-
surement, which has a difference in varied research groups, such as the different
percentage of transmittance change (90% or 95%). Therefore, it is difficult to compare
switching time data between different research groups. In recent years, Javier Padilla
and coworkers proposed a standard method for calculating EC switching times. They
fitted the contrast values as a function of pulse length to the following exponential
increase function:
𝛥TM(t) = 𝛥TMmax (1 − e−t∕𝜏 )
where ΔT max represents the full-switch contrast obtained for long pulse lengths
and 𝜏 is the time constant. If switching time t is equal to 𝜏, 63.2% of the maximum
Figure 1.6 The switching 15

time of EC materials. 1.4 to –0.2 V
(a) Electrochemical 10 0.3 s
Current density (mA/cm2)

switching time. Source: 5 treduction
Li et al. [21]. © 2018, Royal
Society of Chemistry (b) 0
Optical switching time.
–5 toxidization
Source: Hsiao et al. [27].
–10
–0.2 to 1.4 V PTTBTPh0.35
–15 0.9 s
–20
–25
165 170 175 180 185 190 195 200 205
(a) Time (s)
40 710 nm
Δ %T = 52%
50 Pulse time = 15 s
90%
Transmittance (%)
60
70
80 tbleaching
tcoloration
90%
90 tb = 1.06 s
tc = 4.23 s
100 On Off
–5 0 5 10 15 20 25 30 35
(b) Time (s)
transmittance change is reached. At a time of 2.3𝜏, 90% ΔTMmax is switched,

identically 95% and 99% of ΔTMmax corresponding to 3𝜏 and 4.6𝜏.
Therefore, for new EC materials, the same chronoabsorptometric responses [28]
should be measured and fitted to the aforementioned function. From the fittings, the
max values of ΔTMmax (the contrast corresponding to a full switch), the time con-
stant 𝜏, and the corresponding regression coefficient r 2 will be obtained. Afterwards
the switching time t90% or t95% will be easily calculated. This method allows an easy
direct comparison between different reported values.
1.3.3 Coloration Efficiency

Coloration efficiency (CE) plays a fundamental role in the evaluation of the effi-
ciency of charge utilization during the EC processes. It relates the optical
absorbance change of an EC material at a given wavelength (ΔA) to the density
of injected/ejected electrochemical charge necessary to induce a full switch (Qd ).
The higher CE value indicates a large transmittance change with a small amount
of charge, which makes more effective use of the injected charge. CE value can be
10 1 Introduction
50
40
30
Current (mA)
20
10 Qd = 9.75 mC/cm2
–10
–20
0 5 10 15 20 25 30
Time (s)
Figure 1.7 The calculation of Qd . Source: Hsiao et al. [27].
calculated using the following equation:

( )
T
log T ox
𝛥A neut
CE = =
Qd Qd
where T ox and T neut are the transmittances in the oxidized and neutral states, respec-
tively, and Qd represents the injected/ejected charge per unit area, which could be
obtained from the integral area of the current density curve during voltage switching
(Figure 1.7).
Very similar to the previous parameters contrast and switching time, the CE values
are also different depending on the selective wavelength, as shown in Figure 1.8.
Several kinds of CE value of the same EC materials are exhibited: in most reported lit-
erature, the CE of characteristic wavelength reaching the maximum contrast (𝜆max )
is calculated, which is the maximum CE value (CEmax ). Also, the CE value at 555 nm
100 200
CE
90
Coloration efficiency (CE) (cm2/C)
TMVIS, bleached = 77%

80
150
70
Transmission (%)
60
50 100
40
TMVIS, colored = 8% CEmax, at 767 nm = 188 cm2/C
30
CE at 550 nm = 66 cm2/C 50
20
Photopic CE = 75 cm2/C
10
0 0
400 450 500 550 600 650 700 750
Wavelength (nm)
Figure 1.8 Different types of CE value of the same EC materials. Source: Kraft [25].
is calculated for comparison in different publishes because of the highest sensitivity

of human eyes at 555 nm as well as the photopic CE based on the photopic trans-
mittance mentioned in the contrast part, which considered the light transmission
over the wavelength range between 380 and 780 nm normalized with the spectral
sensitivity of the human eye. Therefore, more plot of CE values should be obtained
rather than single-valued CE values, to give more information about the perfor-
mance of EC materials.
In addition, when insightfully considering the injected/ejected charge Qd , we
can find it in fact to consist of three part: faradaic charge QF associated with
doping/de-doping, capacitive charge QC due to the capacitive nature of the ECD,
and parasitic charge QP associated with electrolyte/impurity reactions. Among
them, the faradaic charge is the source of redox activity leading to chromic change
actually. Therefore, Fabretto et al. reported a new technique for measuring CE by
extracting the faradaic charge from the total charge and calculated the only faradaic
charge-based CE value [29]. As we discussed, the total charge flow is simply the
addition of the three individual charge flows and is given by
Qd = QF + QC + QP
where the parasitic current was a small component (approximately <2%) compared
with the other two and therefore can be ignored. Then the time–evolution total
current flow can be described as following:
nFAC0 D1∕2 −1∕2
Id (t) = IF (t) + IC (t) = t + I0 e−t∕RC = k t−1∕2 + I0 e−t∕RC
𝜋
where n is the number of electrons transferred per molecule, F is the Faraday con-
stant (96 500 C/mol), A is the electrode area (cm2 ), C0 is the concentration of species
in the bulk solution (mol/cm3 ), D is the apparent diffusion coefficient (cm2 /s), t is
time in seconds, I 0 is the maximum current flow at t = 0, R is the cell resistance, and
C is the double layer capacitance. Then fitting the experimental data to this equation
and substituting the constant k, at last, a plot of the time–evolution faradaic current
will be obtained, and the corresponding faradic-corrected CEs can be calculated.
Usually, the faradic-corrected CEs are larger than the uncorrected results, because
the total charge ingress/egress (i.e. Qd ) is larger than the faradic charge (i.e. QF).
1.3.4 Optical Memory

The optical or EC memory (also called open-circuit memory) of an EC material
can be defined as the propensity of the material to retain its redox/colored state
upon removing the external bias. Usually, the memory effect are often observed
in film-state EC materials such as conjugated polymers, which well adhered onto
the electrode, and hence restrict the movement of the electrons. In contrast, some
solution-based ECDs (e.g. viologens) will exhibit a self-erasing effect, which means
the colored state disappeared rapidly in the absence of applied voltage because the
electrons diffuse freely in this type of device. The memory effect is useful for the
energy-saving devices and also can be applied for data storage. Figure 1.9 shows
12 1 Introduction
70 Figure 1.9 Open-circuit memory

1.0 V
tests of PBOTT-BTD spray coated
–0.2 V
60 on an ITO-coated glass slide in
Transmittance (%)
0.1 M TBAPF6/ACN at 423 nm:

50 (a) short- and (b) long-term
performance. Source: Li et al. [21].
40
30
20
10
0 100 200 300 400 500 600
Time (s)
(a)
70
1.0 V
60 –0.2 V
Transmittance (%)
50
40
23% 20%
30
20
10
0 600 1200 1800 2400 3000 3600
(b) Time (s)
an optical memory test. The short-term memory was investigated by applying a

potential pulse for 2 seconds prior to forming the open-circuit state for 100 seconds;
the transmittance change at 423 nm was monitored simultaneously (Figure 1.9a).
Then a long-term memory is also studied by applying a potential for two seconds
and removing the bias for one hour (Figure 1.9b). The EC conjugated polymers
remain in the initial transmittance contrast well in the absence of an applied
voltage, which exhibits a good optical memory.
1.3.5 Stability
In most cases of laboratory study, researchers record the number of redox cycles
that an EC material stand without significant loss in the performance as the
electrochemical stability, irreversible oxidation or reduction at extreme poten-
tials, side reactions with water or oxygen, and heat release in the system during
switches may cause the degradation of electrochemical stability. Usually, the
charge density Qd recorded under electrochemical cycling is up to 104 –106 , as
shown in Figure 1.10a. The charge density of a Ti-doped V2 O5 EC film haven’t
changed through 2 × 106 cycles; meanwhile the transmittance change at a certain
wavelength during continuous cycling is also important to describe the stability
Figure 1.10 Charge density 16

(a) and transmittance
(b) variation curves of ECD 12
with the cycle number 8
Charge density (mC/cm2)

K : 1000. Source: Wei
et al. [30]. 4
Charge
0 Discharge
–4
–8
–12
–16
0 40 80 120 160 200
(a) Cycle number (K)
80
70
60
Transmittance (%)
50
680 nm
40 900 nm
30 Bleached solid line

Colored dot line
20
10
0
0 40 80 120 160 200
(b) Cycle number (K)
of an EC material. Such as shown in Figure 1.10b, the transmittance of the ECD

remains stable through 200 000 cycles. Actually, the CE change after numerous
cycles also can be used to evaluate the long-term stability of EC materials, because
it contains information of both transmittance and charge density.
However, if we consider the real application of ECD in building windows, there
are more strict conditions for durability and reliability. For instance, a lifetime
over 20 years with more than 106 switching cycles is necessary. Extreme weather
conditions such as temperatures below −20 ∘ C and above +40 ∘ C are huge challenge
for both EC materials and electrolytes, as well as other degradation factors such
as high solar irradiation levels, fast temperature changes, uneven temperature
distribution and additional stresses, rain, humidity, mechanical shock, and drying.
Therefore, in 1998, Carl M. Lampert proposed a standard test guideline for industry
application of EC [31], as shown in Figure 1.11. Recently, the International Organi-
zation for Standardization (ISO) also has launched an international standard: Glass
in building – Electrochromic glazings – accelerated aging test and requirements
(ISO 18543) for EC use in buildings.
14 1 Introduction
EC color/bleach cycling 1. 25 000 cycles at 25 °C

2. 10 000 cycles at – 20 °C
3. 25 000–100 000b cycles with UVa at 65 °C
UVa stability Prolonged cycles (12 h colored, 12 h bleach) for a total exposure of
6000 MJ/m2, UV intensity integrated between 300 and 400 nm
Heat storage 500 h at 90 °C
Low temperature storage 1000 h at 20 °C to – 30 °C
Humidity/temperature storage 1000 h at 70 °C, 90% humidity
Thermal cycling 85 °C for 4 h, followed by – 40° C for 4 h and followed by 37 °C for 16 h
at 100% R.H. (4 h of ramp between each condition) (repeat
four times)
Thermal shock One hour colored and one hour bleached. Test in a UV chamber, with
UVa lamp on during coloration. Spray with 25 °C water in bleached
state (24 cycles)
a
Black panel temperature during the bright periods of 60 °C, and 25 °C in the dark periods.
b
Asahi has used up to 100 000 cycles.
Figure 1.11 Recommended testing guidelines for EC windows for exterior architectural
applications. Source: Lampert et al. [31].
1.4 Conclusion
In this chapter, a broad overview of electrochromism, EC materials, device struc-
ture, development history, and key parameters of electrochromism have been
introduced briefly. More detailed descriptions of each area will be discussed in
Chapters 2–15. In summary, research in EC technologies has achieved significant
breakthroughs over the decades. Many generations of EC materials have been
developed, ranging from traditional metal oxides to more recent organic polymers,
small molecules, and hybrid materials. Moreover, benefit from the ECD design and
structural optimization, flexible substrate-based devices were fabricated with the
low-price roll-to-roll process, which makes the EC technology have large scope
applications, such as smart windows for reducing building energy consumption,
self-powered EC window using organic photovoltaic cells as power supplement, car
rear-view mirrors for greater safety, and smart sunglasses for better UV-radiation
protection. Many of these technologies and applications have been commercialized
and are available on the market. With the concerted efforts of researchers and
engineers, we believe that the new EC materials and advanced technologies will
constantly develop and more advanced ECD with low manufacturing cost will be
exploited to realize practical applications.
References
1 Fletcher, S. (2015). The definition of electrochromism. Journal of Solid State Elec-

trochemistry 19 (11): 3305–3308.
2 Camurlu, P. (2014). Polypyrrole derivatives for electrochromic applications.
RSC Advances 4 (99): 55832–55845.
3 Wang, Z., Wang, X., Cong, S. et al. (2020). Fusing electrochromic technology
with other advanced technologies: a new roadmap for future development.
Materials Science & Engineering R: Reports 140.
References 15
4 Wu, W., Wang, M., Ma, J. et al. (2018). Electrochromic metal oxides: recent
progress and prospect. Advanced Electronic Materials 4 (8).
5 Mortimer, R.J. (2011). Electrochromic materials. Annual Review of Materials
Research 41 (1): 241–268.
6 Platt, J.R. (1961). Electrochromism, a possible change of color producible in dyes
by an electric field. The Journal of Chemical Physics 34 (3): 862–863.
7 Hutchison, M.R. (1913). Electrographic display apparatus and method. US Patent
1,068,774, filed 29 July 1913.
8 Lehovec K. (1957). Photon modulation in semiconductors. US Patent 2,776,367,
filed 1 January 1957.
9 Neff, V.D. (1978). Electrochemical oxidation and reduction of thin-films of
prussian blue. Journal of the Electrochemical Society 125 (6): 886–887.
10 Michaelis, L. and Hill, E.S. (1933). The viologen indicators. The Journal of
General Physiology 16 (6): 859–873.
11 Schoot, C.J., Ponjee, J.J., van Dam, H.T. et al. (1973). New electrochromic
memory display. Applied Physics Letters 23 (2): 64–65.
12 Garnier, F., Tourillon, G., Garzard, M., and Dubois, J.C. (1983). Organic conduct-
ing polymers derived from substituted thiophenes as electrochromic material.
Journal of Electroanalytical Chemistry 148: 299–303.
13 Mengoli, G., Musiani, M.M., Schreck, B., and Zecchin, S. (1988). Electrochemical
synthesis and properties of polycarbazole films in protic acid media. Journal of
Electroanalytical Chemistry and Interfacial Electrochemistry 246 (1): 73–86.
14 Zheng, H.B., Lu, W., and Wang, Z.Y. (2001). Electrochemical and electrochromic
properties of poly(ether naphthalimide)s and related model compounds. Polymer
42 (8): 3745–3750.
15 Oishi, Y., Takado, H., Yoneyama, M. et al. (1990). Preparation and properties
of new aromatic polyamides from 4,4′ -diaminotriphenylamine and aromatic
dicarboxylic acids. Journal of Polymer Science Part A: Polymer Chemistry 28 (7):
1763–1769.
16 Cheng, S.-H., Hsiao, S.-H., Su, T.-H., and Liou, G.-S. (2005). Novel aromatic
poly(amine-imide)s bearing a pendent triphenylamine group: synthesis, thermal,
photophysical, electrochemical, and electrochromic characteristics. Macro-
molecules 38 (2): 307–316.
17 Arimoto, F.S. and Haven, A.C. (1955). Derivatives of dicyclopentadienyliron.
Journal of the American Chemical Society 77 (23): 6295–6297.
18 Whittell, G.R. and Manners, I. (2007). Metallopolymers: new multifunctional
materials. Advanced Materials 19 (21): 3439–3468.
19 Wade, C.R., Li, M., and Dincă, M. (2013). Facile deposition of multicolored
electrochromic metal–organic framework thin films. Angewandte Chemie Interna-
tional Edition 52 (50): 13377–13381.
20 Hao, Q., Li, Z.-J., Lu, C. et al. (2019). Oriented two-dimensional covalent organic
framework films for near-infrared electrochromic application. Journal of the
American Chemical Society 141 (50): 19831–19838.
21 Li, W., Ning, J., Yin, Y. et al. (2018). Thieno[3,2-b]thiophene-based conjugated
copolymers for solution-processable neutral black electrochromism. Polymer
Chemistry 9 (47): 5608–5616.
16 1 Introduction
22 Beaujuge, P.M. and Reynolds, J.R. (2010). Color control in π-conjugated organic
polymers for use in electrochromic devices. Chemical Reviews 110 (1): 268–320.
23 Jiang, M., Sun, Y., Ning, J. et al. (2020). Diphenyl sulfone based multicolored
cathodically coloring electrochromic materials with high contrast. Organic
Electronics 83: 105741.
24 Fred Schubert, E., Chapter 16. Human Eye Sensitivity and Photometric Quantities
in Light-Emitting Diodes, 2e. Cambridge University Press.
25 Kraft, A. (2018). Electrochromism: a fascinating branch of electrochemistry.
ChemTexts 5 (1): 1–18.
26 Padilla, J., Seshadri, V., Filloramo, J. et al. (2007). High contrast solid-state elec-
trochromic devices from substituted 3,4-propylenedioxythiophenes using the dual
conjugated polymer approach. Synthetic Metals 157 (6–7): 261–268.
27 Hsiao, S.-H. and Lin, S.-W. (2016). Electrochemical synthesis of electrochromic
polycarbazole films from N-phenyl-3,6-bis(N-carbazolyl)carbazoles. Polymer
Chemistry 7 (1): 198–211.
28 Hassab, S., Shen, D.E., Österholm, A.M. et al. (2018). A new standard method to
calculate electrochromic switching time. Solar Energy Materials and Solar Cells
185: 54–60. https://doi.org/10.1016/j.solmat.2018.04.031.
29 Fabretto, M., Vaithianathan, T., Hall, C. et al. (2008). Faradaic charge corrected
colouration efficiency measurements for electrochromic devices. Electrochimica
Acta 53 (5): 2250–2257.
30 Wei, Y., Zhou, J., Zheng, J., and Xu, C. (2015). Improved stability of elec-
trochromic devices using Ti-doped V2 O5 film. Electrochimica Acta 166: 277–284.
31 Lampert, C.M., Agrawal, A., Baertlien, C., and Nagai, J. (1999). Durability evalu-
ation of electrochromic devices – an industry perspective. Solar Energy Materials
and Solar Cells 56 (3): 449–463.
17
Advances in Polymer Electrolytes for Electrochromic

Applications
2.1 Introduction
The ionic conduction medium between the electrodes and electrochromic (EC)
materials is an electrolyte, which is one of the most essential active components
in electrochromic device (ECD). Electrolyte provides an indispensable role as the
prime ionic conduction medium between the electrodes while preventing electron
conduction between the two electrodes during EC operation. The important
electrolyte properties greatly affecting the EC performance are the electrolyte ionic
conductivity, ion dissociation, transport rate of ion through bulk and interface,
and thermal stability [1]. Electrolytes were initially reported in the early 1970s,
including ceramic, glass, crystalline, and polymer electrolytes (PEs). PE was first
introduced by Fenton et al. in 1973 [2] and widely applied since 1980s [3]. In the
past decades, PEs attracted much attention from all over the world’s researchers
due to their promising applications in electrochemical storage/conversion devices.
In general, electrolytes can be classified into PEs, liquid electrolytes, ceramic elec-
trolytes, and solid inorganic electrolytes [4–6]. Briefly, PE is a membrane composed
of a dissolution of salts in a polymer matrix with high molecular weight [7]. PE is
widely applied in electrochemical devices such as solid-state batteries and recharge-
able batteries, ECDs, supercapacitors, fuel cells, dye-sensitized solar cells, and EC
windows. Technologically, PEs evolved from polymer, liquid ionic conductor and
solid-state ionic conductor. PEs can be prepared by dissolving metal salts in polar
polymer hosts, which could be used to replace the liquid ionic solution. Liquid elec-
trolytes possessing high ionic conductivity have several inevitable drawbacks such
as the possibility of electrolyte leakage, low chemical stability, hydrostatic pressure
considerations, and difficulty in assured sealing and are unsafe for practical applica-
tions especially in scaling-up processes [8]. Comparing with liquid electrolytes, PE
has several prominent advantages, such as high ionic conductivity, safety, flexibility,
wide electrochemical windows, and so on [9, 10].
Organic Electronics for Electrochromic Materials and Devices, First Edition. Hong Meng.
© 2021 WILEY-VCH GmbH. Published 2021 by WILEY-VCH GmbH.
18 2 Advances in Polymer Electrolytes for Electrochromic Applications
2.2 Requirements of Polymer Electrolytes

in Electrochromic Applications
Factors that lead to the use of PE in an EC devices are as follows (Figure 2.1).
● High optical transparency

High optical transparent PEs are highly desirable for EC applications. High trans-
mittance enhances the transparency of an EC device in the bleached state. Elec-
trolytes cannot affect the optical shifts during colored and bleached states.
● Flexible and mechanically stretchable
PE owing to flexible and mechanically stretchable advantages can be better
applied in ECDs, especially in flexible and stretchable devices. The polymeric
matrix is of vital importance. The PE requires to keep mechanical stability during
bending and stretching states.
● Multifunctional separator
There is a direct contact between the two electrodes without any separator, which
will lead to a short circuit. PE can act as a separator layer in an EC device, making
these devices light and compact without the need for additional separators. More-
over, PEs demand intimate binding effect, making favorable electrical contact with
the electrodes and good adherence to EC layers.
● Wide range of working temperature
PEs inherently exhibit the ability to operate over a wide range of temperature as
compared to the other counterparts.
● Cation coordination ability
High
stability,
reversible, High ionic
and conductivity
Wide operation
potential reliable
window
Easy to
synthesize with
Cation low cost
coordination Main
ability concerns in
electrolyte Highly optical
transparent
Wide range of
working
temperature
Flexible and
mechanically
Chemical, and stretchable
electrochemical
stability Multifunctional
separator
Figure 2.1 Main concerns in electrolyte.

2.2 Requirements of Polymer Electrolytes in Electrochromic Applications 19
Polymers in electrolytes with benign cation coordination ability can better make
for coordination bonding interactions with the metal cations.
● Wide operation potential window
Stable electrochemical window is the range of working potential in an EC device
without breakdown of electrolyte itself. The maximum potential is determined
by the potential of the oxidation reaction. Meanwhile, the minimum potential is
determined by the potential of the reduction reaction. To ensure the long-time and
cycling stability of the ECD, the working potential window of a device should be
considered in the electrochemical operating range of the electrolyte.
● Thermal, photo, chemical, and electrochemical stability
An ideal PE should possess good thermal and photo stability. During electro
chromic processes, the device may release heat, which may result in degradation
of the EC devices. Similarly, an ideal electrolyte with photo stability prevents
device from being destroyed via prolonged exposure to air. It is necessary to
keep good electrochemical stability in the voltage range for ECDs. Undesired
interaction effects between the EC layer and electrolyte should not exist in the
ECD during EC processes so that devices can keep reversible and long lifetime
performance for practical application. This chemical stability must be ensured
both during the deposition and during the cycling processes. Currently, small
molecule EC materials-based ECDs have appeared in lots of researches. However,
this kind of ECD mostly can be operated under higher potential. Therefore, PEs
with wide potential window are demanded.
● High ionic conductivity (>10−4 S/cm) with low electronic conductivity
PEs should be a good ionic conductor and electronically insulating (𝜎 e
< 10−12 S/cm) so that ion transport could be facilitated to minimize self-discharge.
In EC process, the essence of color change is the transfer of ions into and out of an
EC film. The electrolyte should also maintain its high ionic conductivity even after
thousands of cycles. The flexibility of polymer matrix chains in the amorphous
phase allows ions to be transported frequently. This easy transport of ions is
hindered in the crystalline phase, where the material is densely packed and there
is not enough space to allow rapid transport of ions [11]. The ion transference
number is important in the characterization of PEs. A large transference number
can reduce concentration polarization of electrolytes during charge–discharge
steps [12].
● Easy to synthesize with low cost
The price of PE cannot be the factor of resulting in hindering practical application.
Inexpensive, easily available PEs are highly necessary for the successful commer-
cialization and implementation of EC devices. It is worth mentioning that the
thickness of PE film should be controlled and easy to operate.
● Safe and environmentally friendly
Safe and environmentally friendly are highly desirable for practical application
of the ECDs. So far, ECDs have been widely used in people’s daily lives, such as
EC glasses, car mirrors, and cockpit glasses. A nontoxic, environmental, and recy-
clable electrolyte is a top priority in an EC device, which cannot jeopardize our
health.
2.3 Types of Polymer Electrolytes

PEs are formed by dispersing a salt into a neutral polymer matrix. The composition
of the matrix plays a great role in mechanical strength, electrolyte/active material
contact, flexibility, and processability in ECDs. PEs applied for ECDs can be mainly
classified into gel polymer electrolytes (GPEs), self-healing PEs, cross-linking poly-
mer electrolytes (CPEs), ceramic PEs, ionic liquid (IL) PEs, and gelatin-based PEs.
2.3.1 Gel Polymer Electrolytes (GPEs)

GPE also known as plasticized PE was first introduced by Feuillade and Perche
in 1975 [13]. GPEs are usually synthesized by incorporating a larger quantity of
liquid plasticizer and/or solvents into a polymer matrix to form a stable gel with
the polymer host structure, having relatively higher ambient-temperature ionic
conductivity [14]. Generally, GPE consists of an ionically conducting medium
polymer such as poly(ethylene oxide) (PEO) and a metal salt (lithium) swollen
with a suitable solvent. GPE could exhibit fast ion diffusive nature and cohesive
properties comparable to solids [15]. The first one is known for its high conductivity
with the H+ donors originating from, e.g. sulfuric (H2 SO4 ) or phosphoric (H3 PO4 )
acid [16]. In the second group mobile Li+ species are provided by dissolution of
lithium perchlorates (LiClO4 ) [17], triflates (LiCF3 SO3 ) [18], fluorophosphates
(LiPF6 ) [19], or fluoroborates (LiBF4 ) [20] in protic solvents (propylene, acetonitrile
[ACN], ethylene carbonates, etc.). As was reported, binary or ternary solvents,
such as EC + PC and DMC + PC + EC, were also employed [21, 22]. These types
of electrolytes are characterized by a higher ambient ionic conductivity but poor
mechanical properties. Although most PGEs have high ionic conductivity of
10−3 S/cm at room temperature, poor mechanical properties and considerable
viscosity inevitably result in internal short circuit and cell leakage. UV and heat
irradiation are other potential factors for degradation of electrolytes. Plasticizers
such as PC, EC, diethyl carbonate (DEC), and dimethyl carbonate (DMC) can be
applied in developing the physical characteristics of the overall blend. Plasticizers
improve the ionic conductivity by increasing the amorphous phase content,
dissociating ion aggregates, increasing ionic mobility within the gel electrolytes,
or lowering the glass transition temperature (T g ) of the system [23]. The balance
between increasing ionic conductivity and decreasing mechanical strength needs to
be maintained while plasticization occurs. Gel electrolytes have been used in many
applications but most of recent published papers are about EC applications. In the
GPE, the immobilized solvent in the polymer matrix has strong effects on the ionic
conductivity. So far, PEO, poly methyl methacrylate (PMMA), poly(vinylidene fluo-
ride) (PVDF), poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP), and
poly acrylonitrile (PAN)-based gel electrolytes have aroused researchers’ interests
[24, 25]. Recently, some of gel electrolytes have aroused researchers’ interests, such
as poly ethylene oxide (PEO), polyethylene glycol (PEG) [26], boronate esters [27],
sodium polystyrene sulfonate [28], waterborne polyurethane, [29] polyester and
PEO [30], polyvinyl alcohol (PVA), PAN, PMMA, poly(ethyl methacrylate) (PEMA)
and poly(2-ethoxyethyl methacrylate) (PEO EMA), [31] poly vinyl chloride (PVC),
poly(vinyl sulfones) (PVS), and PVDF [32].
2.3.1.1 PEO-/PEG-Based Electrolytes

PEO (with a molecular mass above 20 000 g/mol) or PEG (with a molecular
mass below 20 000 g/mol) simply refers to an oligomer or polymer of ethylene
oxide. PEO-based electrolyte is the earliest and most widely studied matrix for
the formation of PE. Since Armand proposed a PE based on polyethylene oxide
(PEO) for lithium batteries in 1978, research in this field has been extensively
carried out [33]. Polyethylene oxide (PEO) has a polar ether group and significant
segment mobility. As a wide range of salt polymers, especially high lithium ion
stable polymers, it has excellent compatibility [34]. But because of high crys-
tallinity, low melting point, limited operating temperature range, low hydroxyl
ion migration number, poor interface characteristics, and other shortcomings, it
fails to achieve the desired effect. In PEO-based electrolytes, the most common
method of increasing ion dissociation is the use of low lattice energy salts and
to add fillers, which may prevent formation of polymer crystals, resulting in
fast ion transportation via an interaction between the fillers and electrolyte [35].
PEO–H3 PO4 and (PEO)8 –LiClO4 were studied for electrochromism in devices [36].
However, the low Li+ conductivity inhibits its applicability. Later, PEO–LiS O3 CF3
and PEO–LiN (SO2 CF3 )2 were reported to reach higher ion conductivities [37, 38].
PEO used as electrolyte in the gel form with an ionic conductivity of 2 mS/cm
was reported in WO3 film ECD, which exhibited superior EC performance and
memory characteristics [39]. In addition, PEO-based GPE plasticized with ethylene
carbonate/propylene carbonate or N-butyl-3methylpyridinium trifluoromethane
sulfonylimide (PTFSI) has been studied by Desai et al. for the ECD [40]. Ionic
conductivity can be significantly enhanced and the phase separation of the PEO
and plasticizer was inhibited. Yang et al. studied the performance of the EC device
prepared using poly(2,5-dimethoxyaniline) (PDMA) and tungsten oxide (WO3 )
as electrode materials and PEO-LiClO4 as GPE plasticized with polycarbonate
[41]. Similarly various other hybrid electrolytes based upon PEO were successfully
applied in EC applications [42].
2.3.1.2 PMMA-Based Polymer Electrolytes

Due to high degree of crystallization, low ionic conductivity at ambient temper-
ature exists in PEO-based PE [43]. PMMA along with PVDF PEs have recently
caused great attention in EC application. PMMA including amorphous phase
and flexible backbone could increase ionic conductivity. As was reported,
PMMA can provide a high transparency, excellent environmental stability,
good gelatinizing properties, high solvent retention ability, and excellent com-
patibility with the liquid electrolytes [44, 45]. Moreover, PMMA shows good
interfacial stability toward electrodes and high solvation ability to form com-
plexation between polymer and salt. Highly ionic conductive PMMA exists as
a gel and is mainly used for electrochromism [45]. Anderson et al. majored
on ECDs with films of W oxide and vanadium pentoxide and an intervening
layer of a PPG–PMMA–LiClO4 [46, 47]. Reynold and coworkers first reported

a polymeric ECD using poly(3,4-proplenedioxythiophene) (PProDOTMe2 ) and
poly[3,6-bis(2-(3,4-ethylenedioxy)-thienyl)-N-methylcarbazole] (PBEDOT-N-MeCz)
as the cathodically and anodically coloring polymers, respectively [48]. In this
device, the EC films were electrosynthesized in poly (3,4-ethylenedioxythiophene)
(PEDOT)-PSS electrodes at the oxidation potential of the monomer, and the
electrolytes were prepared by using PMMA as the novel polymer matrix. The GPE
having composition of 70 : 20 : 7 : 3 (ACN: PC: PMMA: TBAPF6 [tetrabutylam-
monium hexafluorophosphate]) was applied in the ECDs [48]. For the durability
of the device, GPE was evaporated at the edges during the sealing process. The
ECD exhibited a large transmittance change (Δ%T) of 51% at the wavelength of
540 nm and only 5% contrast loss after 32 000 switches. Beaupre et al. reported a
flexible EC cell by using PMMA-LiClO4 electrolyte, which was plasticized with
propylene carbonate to form a highly transparent and conductive gel. Sonmez
et al. has explored a highly transparent and conductive gel with LiClO4 plasticized
with PC, having composition of PC: PMMA (MW: 350.000): LiClO4 (70 : 20 : 7 : 3),
which was applied in EC device [49]. ACN was also added as a high vapor pressure
solvent to make the gel ingredients blend easily. Oral et al. uses similar electrolyte of
LiClO4: ACN: PMMA: PC in the ratio of 3 : 70 : 7 : 20 to study the EC properties [49].
Tung et al. studied the EC properties of the device of PEDOT-Prussian Blue (PB)
using PMMA as GPE [50]. The device exhibited high coloration efficiency and good
long-term cycling stability. Recently, Yang et al. studied a new type of GPE com-
posed of free-standing aramid nanofibers, which was used to fabricate all-solid-state
near-infrared (NIR) ECDs for NIR sheltering applications [51]. This new type of
GPE showed excellent mechanical and heat endurance compared with currently
available GPEs. Kim et al. presented a novel ECD-based photonic device, which can
modulate IR light intensity in a planar optical waveguide ECD by using PMMA gel
electrolyte consisting of 5% (w/w) PMMA, 4% (w/w) phenothiazine, 0.1 m LiClO4 ,
and 11.25 ≈ 10−3 m ferrocene [52]. The results confirm a new approach to consider
ECD-based optical modulators for the development of planar photonic-integrated
circuits and systems.
2.3.1.3 PVDF-Based Polymer Electrolytes

PVDF is another popular host material for electrolytes and has recently been widely
used in ECDs. PVDF offers many advantages, such as good thermomechanical prop-
erties, fairly high permittivity, high hydrophobicity, thermal and chemical stabili-
ties, and chemical resistance. As a semi-crystalline polymer, the PVDF crystalline
phase provides thermal stability, while the amorphous phase provides the flexibil-
ity required for ECDs. PVDF can be soluble in high boiling point and commercial
solvents, such as N-methyl-2-pyrrolidone (NMP) and dimethylformamide (DMF).
However, comparing with lithium salt, PVDF, which is expected to have a low donor
number (DN), is insoluble and cannot be used effectively in polymer salt complexes.
For EC application, PVDF-based PEs have been identified as interesting candidates
and their study is in progress. As was reported by Fabrettos group, an ECD was
prepared by using PVDF for studying the coloration efficiency [53]. P(VDF-TrFE) as
GPE was also studied as potential PE in ECD with polyaniline as EC materials [1].
The gel electrolyte device reached an average ionic conductivity of 2.84 × 10−5 S/cm
and shows stable and reversible light modulation up to 65% in gel state. It was found
that the gel-state device was affected by the number of free ions, while the movement
of ions in the electrolyte bulk and the modulation of light in the semisolid device are
indicated by the electrolyte/EC material interface.
The ionic conductivity of PVDF PEs can be enhanced by incorporating sub-
stantial amounts of plasticizers or combining with IL. Jia et al. have studied
1-butyl-3-methylimidazolium hexafluorophosphate-loaded SCCO2 -treated electro-
spun P(VDF-HFP) membrane as an electrolyte in EC device [54].
Recently, Reynold’s group reported paper-based ECDs consisting of PEDOT:PSS
electrodes and [EMI][TFSI]/PVDF-HFP ion gel electrolyte layer (Figures 2.2 and
2.3) [55]. The ECDs incorporating an ion gel electrolyte were demonstrated where
a magenta-to-colorless device achieves a color contrast (ΔE*) of 56, attributing to
a highly color-neutral bleached state of the extracellular protein (ECP) (a* = −0.5,
b* = 2.9). It was found that the gel-state device was affected by the number of free
ions, while the movement of ions in the electrolyte bulk and the modulation of light
in the semisolid device were indicated by the electrolyte/EC material interface.
R R
O Conductive ink
R O er Electrochromic paper
O O
R pap
ted
O
O O
F-coa O O
O CN m
S S S n
(a) N N
S
n
R R –
SO3
O O
O O
(b) S n
V
R R
R O O R
O O
(c) S S
n
R R
R O O
O R
O
O O
O O
S x S y
(d) N N
S n
Figure 2.2 Schematic showing printing of colored-to-clear electrochromic paper

incorporating cellulose nanofiber (CNF)-coated paper substrates and PEDOT:PSS electrodes
as well as the repeat-unit structures of (a) ECP-Cyan, (b) ECP-Magenta, (c) ECP-Yellow, and
(d) ECP-Black. R = ethylhexyl. Source: Lang et al. [55].
CNF coating Inkjet-printed PEDOT:PSS ECP magenta Ion gel electrolyte +0.8 V
CNF-coated paper Printed electrodes ECP spray casting Blade coating electrolyte Lateral paper ECD
1 2 3 4 5
Figure 2.3 A fabrication process for lateral paper ECDs showing inkjet-printed PEDOT:PSS
electrodes, deposition of ECPs, and [EMI][TFSI]/PVDF-HFP ion gel electrolyte layer. Devices
are operated by applying a 0.8 V bias across the two lateral pixels. Source: Lang et al. [55].
2.3.2 Self-Healing Polymer Electrolytes

A self-healing material is a material that possesses abilities to partially repair dam-
age and restore mechanical properties during its service lifetime [56]. Self-healing
materials are particularly attractive in the field of smart materials because of their
inherent ability to repair cracks, thereby avoiding such risks, reducing waste, and
improving equipment life, durability and reliability. It is believed that the use of
an EC polymer film with self-healing properties would be an effective approach
to overcome the risk of the scar generation in ECDs. Until now, self-healing
polymers based on the Diels–Alder (DA) reaction [57] is an effective method for
the implementation of intrinsic self-healing into functional materials, which have
been explored for various electronic and optoelectronic applications like con-
ducting films [58], organic light-emitting devices [OLEDs] [59], supercapacitors,
etc. [60] Self-healing can come up from the microscopic to macroscopic level.
Some properties in engineering materials may degrade over long time because
of environmental conditions, fatigue or operation damage. Self-healing materials
can address this kind of degradation. The ability to self-heal upon breakdown
or damage depends on various kinds of physical interactions such as hydrogen
bonding [61], π–π stacking [62], ion dipole interaction [63], or chemical interactions
such as disulfide bond [64, 65] and imine bond. [66] They heal autonomously or in
response to a multitude of externally applied stimuli such as pH change, light [67],
electricity, temperature [68], and pressure. Geubelle and coworkers first reported
a completely autonomous man-made self-healing material [69]. Later, an epoxy
system containing microcapsules covered with (liquid thermosetting) monomers
was explored [70]. If a microcrack occurs in the system, the microcapsule breaks
and the crack will be filled by the monomer. This novel self-healing system could
be performed well in polymers and polymer coatings [71].
Zhang and coworkers [72] prepared a dual physically cross-linked hydrogel
containing the hydrogen bonding between poly(acrylamide-co-acrylic acid) and
PVA, hence producing self-healing abilities in hydrogel. As was reported, ion
gels with self-healing performance, which composed of polymer networks and
electrolyte solutions, have attracted great attention [73]. Different strategies
and approaches to devise self-healing materials in ECs have been investi-
gated. For example, multifunctional EC ion gels were enabled by a blend of
active methyl viologen dication in polystyrene-block-poly(methyl methacrylate)-
blockpolystyrene (PS-PMMA-PS) triblock copolymer with ILs [74]. Poly[styrene-
ran-1-(4-vinylbenzyl)-3-methylimidazolium hexafluorophosphate] (P[S-r-VBMI]
[PF6]) random copolymer (Figure 2.4) [75], poly(styrene-ran-methyl methacrylate)
(PS-rPMMA) random copolymer [76], (poly(methyl methacrylate)-b-polystyrene)6
star-shaped block copolymer (Figure 2.5) [77], and poly(vinylidene fluoride-co-
hexafluoropropylene) (PVDF-co-HFP) [78], etc. matrices have been developed
for achieving self-healing solid PEs. The ion conductivity of PVDF-co-HFP-based
polyelectrolytes could be improved by using various PVDF-co-HFP-based polymers
and amorphous polymer electrolytes such as PEG [78], PMMA [79] and poly(vinyl
acetate) (PVAC) [80, 81]. In addition, materials containing IL/polymer blends
S
C ran
y S S
S x
+
AIBN, 80 °C, 30 h
Cl
1 Cl
ran ran S
S y S
N N x y S x
NH4PF6
DMA, 50 °C, 24 h Methanol, 5 h

Cl– PF6–
N+N
2 N +N
3
Figure 2.4 Synthetic routes for P[S-r-VBMI][PF6 ]. Source: Seo and Moon [75].
PS
Bromination ATRP ATRP
Bromoisobutyryl Styrene Methyl methacrylate
PS
bromide
: Cyclodextrin PMMA
100 nm 100 nm 100 nm 100 nm 100 nm

100 nm
BCC HEX PL LAM Asymmetric LAM
Figure 2.5 Synthetic routes for (PS-b-PMMA)18 . Source: Jang et al. [77].
for self-healable EC have been reported in Leong’s group [82]. The interaction of
polymer blends or the inclusion of reaction sites and addition of ILs may induce
rapid healing at lower temperatures, attributing to the increased fluidity and
inhibition of the glass transition temperatures. Moreover, self-healing polymers
based on DA reaction [83] is another effective method for self-healing func-
tional materials. A polymer N-(4-aminophenyl)-N-phenylbenzene-1,4-diamine
maleimide (DATPFMA) was the first report on a bifunctional self-healing EC
polymer, which exhibited superior cyclic stability and colors variations [57]. The
N,N′ -bis(4-aminophenyl)-N,N 0 -diphenyl-1,4-phenylene diamine used as core and
electro-active unit for synthesizing the polymer poly(pentafluorophenyl methacry-
late) (PPFMA) provided more electrochemical active sites to enhance the EC
performance (Figure 2.6) [84]. This DA polymer can also repair cracks by retro-DA
and DA reaction for the self-repair capability [57].
However, developing a material that simultaneously exhibits excellent EC proper-
ties and good self-healing behavior at low temperature is still an unmet challenge,
such as large optical contrast, high coloration efficiency, and long-term, stability, and
fast healing process.
O O
O N N O
O O O N
O O
Heating Cooling
Cooling Heating
0V 0.85 V 1.15 V
Faint yellow Grass green Dark blue
N
O
N O
OH
N
N O O
N N
N
O O
Electrochromic Self-healing
(a)
O O
HO
N N O O
O O
OH HO + N N
O O
N N O O
OH
O O
O PPF O N O
MA PPFMA
(b)
Figure 2.6 (a) The mechanism of self-healing process for electrochromic PPFMA film and
(b) the retro-DA and DA reaction for self-healing polymer PPFMA. Source: Zheng et al. [84].
2.3.3 Cross-linking Polymer Electrolytes (CPEs)

The high ionic conductivity of PEs at low temperature is related to the amorphous
nature of the polymer matrix (Figure 2.7). The cross-linked PEs show good ionic
conductively and amorphous feature [85]. Cross-linking was reported to improve
the dimensional stability and increase the dynamic storage modulus of the PE. This
technique was used to modify positively various PE properties [86, 87], while brittle-
ness, low elasticity, and processability inevitably occur in cross-linked polymer [88].
In the study of lithium salts-based electrolytes, PEO, PMMA, PVC, etc. were com-
monly organized into cross-linked PEs. Matsui et al. have prepared a cross-linked
PE of poly(ethylene oxide) 2-(2-methoxy ethoxy) ethyl glycidyl ether with and with-
out allyl glycidyl ether P(ethylene oxide [EO]/2-(2-methoxyethoxy)ethyl glycidyl
ether [MEEGE]/allyl glycidyl ether [AGE]) complexed in LiN(CF3 SO3 )2 salts [89].
Kuratomi et al. studied a cross-linked copolymer of ethylene oxide and propylene
oxide with LiBF4 or LiN(CF3 SO2 )2 salts [90]. The concentration and anions in
lithium salts are key parameters in determining electrochemical performance. As
was studied, good ionic conductivity and mechanical strength have been exhibited
in a cross-link of high molecular weight poly(oxy ethylene)s PEs [91]. Lee et al.
Figure 2.7 Pictorial model of a preparation of a cross-linked polymer.
have also reported a cross-linked composite PE by polymerizing alkyl monomer

and polyethylene glycol dimethylcrylate (PEGDMA) in LiPF6 /EC [92]. The studies
indicate that ionic conductivity and flexibility of the PEs are dependent on the
monomer content.
In fact, while many conventional ECDs using the EC media of cross-linked poly-
mer gels are exposed to the dynamic range of real-world temperatures, cross-linked
polymer gels may not be optically viable for commercial use due to visual irregular-
ities and/or defects. The patent in 2003 reported a self-healing cross-linked polymer
gel electrolyte used as EC medium, which could solve these detriments and compli-
cations in ECDs [92].
Another intriguing field for the possible application of ionic liquid polymers
(ILPs) is using polymerized ionic liquids (PILs) in ECDs. Among different IL
electrolytes, cross-linked IL PEs have been explored recently. Yan and cowork-
ers reported thermo- and electro-dual responsive ILPs electrolytes, which were
synthesized through the co-polymerization of an ionic liquids monomer (ILM),
3-butyl-1-vinyl-imidazolium bromide ([BVIm][Br]) and N-isopropylacrylamide
(NIPAM) using diallyl-viologen as both the cross-linking agent and the EC mate-
rial, respectively (Figure 2.8) [93]. The electro- and thermo-responsive behaviors
can be found simultaneously under electrical and temperature stimuli, which
demonstrates the application of the dual-response smart window [93].
2.3.4 Ceramic Polymer Electrolytes

Differing from liquid and gel electrolytes, salt in solid-like PEs is dissolved directly
into the solid medium. It is usually a relatively high dielectric constant polymer
(PEO, PMMA, PAN, polyphosphazenes, siloxanes, etc.) and a salt with low lattice
energy.
Multiple advantages of using solid PEs in electrochemical cells are as follows:
(1) Non-volatility.
(2) No decomposition at the electrodes.
(3) No possibility of leaks.
(4) Decreased cell price (such as PEO, PMMA, etc.).
(5) Flexibility.
(6) Lowering the cell weight – solid-based cells do not need heavy steel casing.
(7) Safety.
Many studies have been addressed to incorporate inert oxide ceramics particles
into PE, in order to improve the mechanical properties, reduce polymer crys-
tallinity, and thus solve the problem of low ionic conductivity of solid polymeric
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III
Acaso supo, a mi ver,[394]

y por acierto quereros,
quien tal yerro fue a hacer,
como partirse de veros
donde os dejase de ver.
Imposible es que este tal,
pensando que os conocía,
supiese lo que hacía,
cuando su bien y su mal
junto os entregó en un día.
Acertó acaso a hacer
lo que si por conoceros
hiciera, no podía ser
partirse, y con solo veros
dejaros siempre de ver.
IV
Pues este nombre perdí,[395]

Dido, mujer de Siqueo,
en mi muerte esto deseo
que se escriba sobre mí:
«El peor de los troyanos
dio la causa y el espada;
Dido, a tal punto llegada,
no puso más de las manos.»
V
De la red y del hilado[396]

hemos de tomar, señora,
que echáis de vos en un hora
todo el trabajo pasado.
Y si el vuestro se ha de dar
a los que se pasearen,
lo que por vos trabajaren,
¿dónde lo pensáis echar?
VI
¿Qué testimonios son estos[397]

que le queréis levantar?
Que no fue sino bailar.
¿Esta tienen por gran culpa?
No lo fue a mi parecer,
porque tiene por desculpa
que lo hizo la mujer.
Esta le hizo caer,
mucho más que no el saltar
que hizo con el bailar.
VII
La gente se espanta toda[398]

que hablar a todos distes,
que un milagro que hecistes,
hubo de ser en la boda.
Pienso que habéis de venir,
si vais por este camino,
a tornar el agua en vino,
como el danzar en reír.
VIII
Nadie puede ser dichoso;

señora, ni desdichado,
sino que os haya mirado.
Porque la gloria de veros
en ese punto se quita
que se piensa mereceros.
Así que, sin conoceros,
nadie puede ser dichoso,
señora, ni desdichado,
sino que os haya mirado.
APÉNDICES
I
A LA MUY MAGNÍFICA SEÑORA DOÑA JERÓNIMA PALOVA
DE ALMOGÁVAR, GARCILASO DE LA VEGA[399]
Si no hubiera sabido antes de ahora dónde llega el

juicio de V. m. bastárame para entenderlo ver que os
parescía bien este libro; mas ya estábades tan adelante
en mi opinión que paresciéndome este libro bien hasta
ahora por muchas causas, la principal por donde ahora
me lo paresce es porque le habéis aprobado de tal
manera, que podemos decir que le habéis hecho, pues
por vuestra causa le alcanzamos a tener en lengua que le
entendemos. Porque, no solamente no pensé poder
acabar con Boscán que le tradujese,[400] mas nunca me
osé poner en decírselo, según le vía siempre aborrecer a
los que romanzan libros, aunque él a esto no lo llama
romanzar, ni yo tampoco,[401] mas aunque lo fuera creo
que no se escusara dello mandándolo V. m.
Estoy muy satisfecho de mí, porque antes que el libro
viniese a vuestras manos,[402] ya yo le tenía en tanto como
entonces debía; porque si ahora, después que os parece
bien, empezara a conocerle, creyera que me llevaba el
juicio de vuestra opinión. Pero ya no hay que sospechar
en esto, sino tener por cierto que es libro que merece
andar en vuestras manos para que luego se le parezca
dónde anduvo y pueda después andar por el mundo sin
peligro; porque una de las cosas de que mayor necesidad
hay doquiera que hay hombres y damas principales, es de
hacer, no solamente todas las cosas que en aquella su
manera de vivir acrecienta el punto y el valor de las
personas, mas aun de guardarse de todas las que pueden
abajarle: lo uno y lo otro se trata en este libro tan sabia y
tan cortesanamente que no me parece que hay que
desear en él, sino vello cumplido todo en algún hombre, y
también iba a decir en alguna dama, si no me acordara
que estábades en el mundo para pedirme cuenta de las
palabras ociosas.
Demás de todo esto puédese considerar en este libro
que, como las cosas muy acertadas, siempre se
estienden a más de lo que prometen: de tal manera
escribió el Conde Castellón[403] lo que debía hacer un
singular cortesano, que casi no dejó estado a quien no
avisase de su oficio. En esto se puede ver lo que
perdiéramos a no entenderle.
Y también tengo por muy principal el beneficio que se
hace a la lengua castellana en poner en ella cosas que
merezcan ser leídas, porque yo no sé qué desventura ha
sido siempre la nuestra, que apenas ha nadie escrito en
nuestra lengua sino lo que se pudiera muy bien escusar;
aunque esto sería malo de probar con los que traen entre
las manos estos libros que matan hombres.[404]
Y supo V. m. muy bien escoger persona por cuyo
medio hiciésedes este bien a todos; que siendo, a mi
parecer, tan dificultosa cosa traducir bien un libro como
hacerle de nuevo, diose Boscán en esto tan buena maña,
que cada vez que me pongo a leer este su libro, o por
mejor decir, vuestro, no me parece que le hay escrito en
otra lengua; y si alguna vez se me acuerda del que he
visto y leído, luego el pensamiento se me vuelve al que
tengo entre las manos. Guardó una cosa en la lengua
castellana que muy pocos la han alcanzado, que fue huir
de la afectación, sin dar consigo en una sequedad; y con
gran limpieza de estilo usó de términos muy cortesanos y
muy admitidos de los buenos oídos, y no nuevos ni al
parecer desusados de la gente. Fue, más desto, muy fiel
traductor, porque no se ató al rigor de la letra, como hacen
algunos, sino a la verdad de las sentencias, y por
diferentes caminos puso en esta lengua toda la fuerza y el
ornamento de la otra.[405] Así lo dejó todo tan en su punto
como lo halló, y hallolo tal que con poco trabajo podrían
los defensores deste libro responder a los que quisiesen
tachar alguna cosa dél.[406] No hablo en los hombres de
tan tiernos y tan delicados oídos, que entre mil cosas
buenas que tendrá este libro, les ofenderá una o dos que
no serán tan buenas como las otras; que destos tales no
puedo creer sino que aquellas dos les agradan y las otras
les ofenden, y podríalo probar con muchas cosas que
ellos fuera de esto aprueban. Mas no es de perder tiempo
con estos, sino remitirlos a quien les habla y responde
dentro en ellos mismos, y volverme a los que con alguna
aparencia de razón podrían en un lugar desear
satisfacción de algo que les ofendiese; y es, que allí
donde se trata de todas las maneras que puede haber de
decir donaires y cosas bien dichas a propósito de hacer
reír, y de hablar delgadamente, hay algunas puestas por
ejemplo que paresce que no llegan al punto de las otras ni
merecen ser tenidas por muy buenas de un hombre que
tan avisadamente trató las otras partes; y de aquí podrían
inferir una sospecha de no tan buen juicio ni tanta fineza
del auctor como le damos. Lo que a esto se puede
responder es que la intención del auctor fue poner
diversas maneras de hablar graciosamente y de decir
donaires, y porque mejor pudiésemos conocer la
diferencia y el linaje de cada una de aquellas maneras,
púsonos ejemplo de todas, y discurriendo por tantas
suertes de hablar, no podía haber tantas cosas bien
dichas en cada una destas, que algunas de las que daba
por ejemplo no fuesen algo más bajas que otras; y por
tales creo yo que las tuvo, sin engañarse punto en ellas,
un auctor tan discreto y tan avisado como este. Así que ya
en esto se ve que él está fuera de culpa; yo solo habré de
quedar con una, que es haberme alargado más de lo que
era menester; mas enójanme las sinrazones, y hácenme
que las haga con una carta tan larga a quien no me tiene
culpa.
Confieso a V. md. que hube tanta invidia de veros
merecer sola las gracias que se deben por este libro, que
me quise meter allá entre los renglones o como pudiese; y
porque hube miedo que alguno se quisiese meter en
traducir este libro,[407] o por mejor decir, dañarle, trabajé
con Boscán que sin esperar otra cosa le hiciese luego
imprimir, por atajar la presteza que los que escriben mal
alguna cosa suelen tener en publicarla; y aunque esta
traducción me diera venganza de cualquier otra que
hubiera, soy tan enemigo de cisma, que aun esta tan sin
peligro me enojara; y por esto, casi por fuerza, le hice que
a todo correr le pasase, y él me hizo estar presente a la
postrera lima, más como a hombre acogido a razón que
como ayudador de ninguna enmienda.[408]
Suplico a V. md. que pues este libro está debajo de
vuestro amparo, que no pierda nada por esta poca de
parte que yo dél tomo, pues en pago desto os le doy
escrito de mejor letra donde se lea vuestro nombre y
vuestras obras.[409]
II
CARTA DE GARCILASO AL EMPERADOR CARLOS V[410]
S. C. C. M.t[411]
La orden q̄ el Principe[412] a dado enel caminar de la

gente es q̄ se deſenbarquen enbaya o en saona y de alli
tomen el camino la via de alexandria y paren en medio
desta ciudad y de alexandria lo qual se pone luego en
obra y yo me parto delante para tener prouisto lo
neceſsario en saona.
El capitan sabajosa va alo q̄ el principe y el
embaxador[413] escriuen; lagente q̄ viene segū todos
afirman es muy buena. Nro. Sor. la S. perſona de V. M.t[414]
guarde con acrecētamjēto de nueuos Reynos y srios.[415]
De genoua xx de mayo 1536.
S. C. C. M.t
Criado de V. S. M.t
Garcilaſso.[416]
III
GARSIAE LASSI DE LA VEGA AD FERDINANDUM DE ACUÑA[417]
EPIGRAMMA
Dum Reges, Fernande, canis, dum Caesaris altam

Progeniem nostri, claraque facta Ducum,
Dum Hispana memoras fractas sub cuspide gentes,
Obstupuere homines, obstupuere Dei:
Extollensque caput sacri de vertice Pindi
Calliope blandis vocibus haec retulit;
Macte puer gemina praecinctus tempora lauro,
Qui nova nunc Martis gloria solus eras;
Hac tibi dat Bacchusque pater, dat Phoebus-Apollo
Nympharumque leves Castalidumque chori,
Ut quos divino celebrasti carmine Reges,
Teque simul, curva qui canis arma lyra,
Saepe legant, laudent, celebrent post fata Nepotes:
Nullaque perpetuos nox fuget atra dies.
IV
OCTAVA RIMA
«Cristóbal de Castillejo, poeta de agudo ingenio en su

tiempo, da el nombre de poeta solamente al nuestro —a
Garcilaso— fol. 27 de sus obras, y da por suya, fol. 275,
esta octava rima:
Y ya que mis tormentos son forzados,

Aunque vienen sin fuerza consentidos
¿Pues qué mayor alivio [a] mis cuidados
que ser por vuestra causa padecidos?
Si como son por vos bien empleados,
De vos fuesen, señora, conocidos,
La más crecida angustia de mi pena
Sería de descanso y gloria llena.»
(Don Tomás Tamayo de Vargas, Garcilaso de la Vega,

Madrid, 1622, fol. 86 de las anotaciones.)
V
ANÉCDOTA
«Garcilaso, como era un caballero muy cortesano, y el

doctor Villalobos un muy del palacio y gracioso médico,
así muy ordinariamente —es decir, frecuentemente—
ambos se burlaban; y habiendo estado muy malo
Garcilaso, curole el dotor y sanole muy cuidadosamente; y
viendo que un día y otro se tardaba la paga, enviole un
paje el dotor, que pues le había hecho tanto mal como
volverle al mundo, que le pagase. Él —Garcilaso—
abriendo un arca vacía, sacó della también una bolsa
vacía, y enviósela con esta copla dentro:
La bolsa dice: —Yo vengo

Como el arca de moré,
Que es el arca de Noé
Que quiere decir: no tengo.»
(Miscelánea de don Luis Zapata, tomo XI del Memorial

histórico español, pág. 297.) De este mismo juego de
vocablos: Noé = no he = no tengo, usó también Barahona
de Soto en su paradoja A la pobreza y Luis Rufo en Las
quinientas apotegmas. (V. F. Rodríguez Marín, Luis
Barahona de Soto, Madrid, 1903, págs 739-740.)
Í N D I C E A L FA B É T I C O
DE PRI MERO S VER SO S
Págs.
Acaso supo a mi ver, Versos cortos III. 257

A Dafne ya los brazos le crecían, Soneto XIII. 220
A la entrada de un valle, en un desierto, Soneto XXXVI. 252
Amor, amor, un hábito vestí, Soneto XXVII. 237
Aquella voluntad honesta y pura, Égloga III. 123
Aquí, Boscán, donde del buen troyano, Elegía II. 159
Aunque este grave caso haya tocado, Elegía I. 145
Boscán, las armas y el furor de Marte, Soneto XXXV. 250
Boscán, vengado estáis, con mengua mía, Soneto XXVIII. 239
Clarísimo Marqués, en quien derrama, Soneto XXI. 228
Como la tierna madre que al doliente, Soneto XIV. 221
Con ansia estrema de mirar qué tiene, Soneto XXII. 229
Con tal fuerza y vigor son concertados, Soneto XX. 227
Con un manso ruido, Canción III. 183
Cuando me paro a contemplar mi estado, Soneto I. 205
Culpa debe ser quereros, Versos cortos I. 255
De aquella vista pura y ecelente, Soneto VIII. 215
De la red y del hilado, Versos cortos V. 258
Dentro en mi alma fue de mí engendrado, Soneto XXXI. 243
Echado está por tierra el fundamento, Soneto XXVI. 235
El aspereza de mis males quiero, Canción IV. 187
El dulce lamentar de dos pastores, Égloga I. 1
En fin, a vuestras manos he venido, Soneto II. 207
En medio del invierno está templada, Égloga II. 27
En tanto que de rosa y azucena, Soneto XXIII. 231
Escrito está en mi alma vuestro gesto, Soneto V. 211
Estoy contino en lágrimas bañado, Soneto XXXII. 245
Gracias al cielo doy que ya del cuello, Soneto XXXIV. 248
Hermosas ninfas, que en el río metidas, Soneto XI. 218
Ilustre honor del nombre de Cardona, Soneto XXIV. 232
226
Julio, después que me partí llorando, Soneto XIX.
La gente se espanta toda, Versos cortos VII. 259
La mar en medio y tierras he dejado, Soneto III. 208
La soledad siguiendo, Canción II. 179
Mario, el ingrato amor, como testigo, Soneto XXXIII. 246
Mi lengua va por do el dolor la guía, Soneto XXXVII. 253
Nadie puede ser dichoso, Versos cortos VIII. 260
No las francesas armas odiosas, Soneto XVI. 223
No pierda más quien ha tanto perdido, Soneto VII. 214
¡Oh hado esecutivo en mis dolores, Soneto XXV. 234
¡Oh dulces prendas, por mi mal halladas, Soneto X. 217
Pasando el mar Leandro el animoso, Soneto XXIX. 240
Pensando que el camino iba derecho, Soneto XVII. 224
Por ásperos caminos he llegado, Soneto VI. 212
Pues este nombre perdí, Versos cortos IV. 257
¿Qué testimonios son estos, Versos cortos VI. 258
Señora mía, si de vos yo ausente, Soneto IX. 216
Señor Boscán, quien tanto gusto tiene, Epístola. 169
Si a la región desierta, inhabitable, Canción I. 175
Si a vuestra voluntad yo soy de cera, Soneto XVIII. 225
Si de mi baja lira, Canción V. 197
Siento el dolor menguarme poco a poco, Soneto XXXVIII. 254
Si para refrenar este deseo, Soneto XII. 219
Si quejas y lamentos pueden tanto, Soneto XV. 222
Sospechas, que en mi triste fantasía, Soneto XXX. 242
Un rato se levanta mi esperanza, Soneto IV. 210
Yo dejaré desde aquí, Versos cortos II. 256
ÍNDICE GENERAL
Págs.
Introducción. vii
Datos bibliográficos. xxi
ÉGLOGAS
I.—El dulce lamentar de dos pastores. 1
II.—En medio del invierno está templada. 27
III.—Aquella voluntad honesta y pura. 123
ELEGÍAS
I.—Aunque este grave caso haya tocado. 145
II.—Aquí, Boscán, donde del buen troyano. 159
EPÍSTOLA
Señor Boscán, quien tanto gusto tiene. 169
CANCIONES
I.—Si a la región desierta, inhabitable. 175
II.—La soledad siguiendo. 179
III.—Con un manso ruído. 183
IV.—El aspereza de mis males quiero. 187
V.—Si de mi baja lira. 197
SONETOS
I.—Cuando me paro a contemplar mi estado. 205
II.—En fin, a vuestras manos he venido. 207
III.—La mar en medio y tierras he dejado. 208
IV.—Un rato se levanta mi esperanza. 210
V.—Escrito está en mi alma vuestro gesto. 211
VI.—Por ásperos caminos he llegado. 212
VII.—No pierda más quien ha tanto perdido. 214
VIII.—De aquella vista pura y ecelente. 215
IX.—Señora mía, si de vos yo ausente. 216
X.—¡Oh dulces prendas, por mi mal halladas! 217
XI.—Hermosas ninfas, que en el río metidas. 218
XII.—Si para refrenar este deseo. 219
XIII.—A Dafne ya los brazos le crecían. 220
XIV.—Como la tierna madre que al doliente. 221
XV.—Si quejas y lamentos pueden tanto. 222
XVI.—No las francesas armas odiosas. 223
XVII.—Pensando que el camino iba derecho. 224
XVIII.—Si a vuestra voluntad yo soy de cera. 225
XIX.—Julio, después que me partí llorando. 226
XX.—Con tal fuerza y vigor van concertados. 227
XXI.—Clarísimo Marqués, en quien derrama. 228
XXII.—Con ansia estrema de mirar qué tiene. 229
XXIII.—En tanto que de rosa y azucena. 231
XXIV.—Ilustre honor del nombre de Cardona. 232
XXV.—¡Oh hado esecutivo en mis dolores! 234
XXVI.—Echado está por tierra el fundamento. 235
XXVII.—Amor, amor, un hábito vestí. 237
XXVIII.—Boscán, vengado estáis con mengua mía. 239
XXIX.—Pasando el mar Leandro el animoso. 240
XXX.—Sospechas que en mi triste fantasía. 242
XXXI.—Dentro en mi alma fue de mí engendrado. 243
XXXII.—Estoy contino en lágrimas bañado. 245
XXXIII.—Mario, el ingrato amor, como testigo. 246
XXXIV.—Gracias al cielo doy que ya del cuello. 248
XXXV.—Boscán, las armas y el furor de Marte. 250
XXXVI.—A la entrada de un valle, en un desierto. 252
XXXVII.—Mi lengua va por do el dolor la guía. 253
XXXVIII.—Siento el dolor menguarme poco a poco. 254
CANCIONES EN VERSOS CORTOS

I.—Culpa debe ser quereros. 255
II.—Yo dejaré desde aquí. 256
III.—Acaso supo a mi ver. 257
IV.—Pues este nombre perdí. 257
V.—De la red y del hilado. 258
VI.—¿Qué testimonios son estos? 258
VII.—La gente se espanta toda. 259
VIII.—Nadie puede ser dichoso. 260
APÉNDICES
I.—A la muy magnífica señora doña Jerónima Palova de
Almogávar, Garcilaso de la Vega. 261
II.—Carta de Garcilaso al Emperador Carlos V. 269
III.—Garsiae Lassi de la Vega ad Ferdinandum de Acuña,
Epigramma. 271
IV.—Octava rima. 272
V.—Anécdota. 273
Índice alfabético de primeros versos. 275

este libro se acabó de imprimir
en la tipografía de «clásicos castellanos»
el día iii de febrero
del año mcmxi

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2 Advances in Polymer Electrolytes for Electrochromic

3 Electrochromic Small Molecules 49

4 Viologen OEC 105

4.2.4 Viologen-Based Polymer 119

6 Electrochromic Conjugated Polymers (ECPs) 183

6.2.2.1 Steric Effects 192

7 TA-Based Electrochromic Polyimides and Polyamides 269

7.2.2.2 Introduction of Amide Linkage into Polyimide Backbone 285

8 Metallo-Supermolecular Polymers 295

9 Metal-Organic Framework (MOF)- and Covalent Organic

10 Nanostructure-Based Electrochromism 353

10.2.2 Nanostructured Electrochromic Materials in ECs 365

11 Organic Electroluminochromic Materials 373

12 Organic Photoelectrochromic Devices 415

13 Application of OEC Devices 445

13.1.1 The Structure and Working Mechanism of Smart Windows 445

14 Commercialized OEC Materials and Related Analysis of

15 Main Challenges for the Commercialization of OEC 491

Shenzhen, PR China Hong Meng

About the Author

Prof. Dr. Hong Meng obtained his BS in Chemistry at

1.1 General Introduction

Sunlight without atmospheric absorption

Figure 1.2 The scheme of three types of electrochromic devices.

solutions. Therefore many organic small molecules such as viologen, terephthalate

1.2 The History of Electrochromic Materials

Transition metal oxides (TMOs) Conjugated polymers (CPs) Metallo-supermolecular polymers

Figure 1.3 The roadmap of EC materials development.

the development of new TMOs materials, introduction of new nanostructures, and

Benefiting from the bloom and revolution of organic polymers, metallo-super-

1.3 The Key Parameters of Electrochromism

1.3.1 Electrochromic Contrast

–0.2 V 0V 0.2 V 0.4 V

Figure 1.4 The spectroelectrochemistry (SEC) of a black-to-transmissive EC material. (a)

–2.2 V, 425 nm 0 425 nm

0 100 200 300 400 500 600 0 20 40 60 80

Luminous efficiency (lm/W)

Meanwhile, for some broad absorption or color-to-colorless EC materials,

where T photopic is the photopic transmittance, T(𝜆) is the spectral transmittance of

1.3.2 Switching Time