Open AccessArticle

Preparation of Hierarchical Porous ZIF-67 and Its Application in Zinc Battery Separator

Tian Zhao

^1,*

Jiangrong Yu

¹,

Pengcheng Xiao

¹,

Saiqun Nie

¹,

Shilin Peng

¹,

Jiayao Chen

¹,

Fuli Luo

¹,

Christoph Janiak

and

Yi Chen

^1,*

School of Packaging and Material Engineering, Hunan University of Technology, Zhuzhou 412007, China

Institut für Anorganische Chemie und Strukturchemie, Universität Düsseldorf, Universitätsstr. 1, D-40225 Düsseldorf, Germany

Authors to whom correspondence should be addressed.

Chemistry 2024, 6(6), 1363-1373; https://doi.org/10.3390/chemistry6060080

Submission received: 18 September 2024 / Revised: 23 October 2024 / Accepted: 29 October 2024 / Published: 31 October 2024

(This article belongs to the Special Issue Nano/Micro MOF-Based Materials for Energy Conversion and Storage)

Download

Browse Figures

Versions Notes

Abstract

This study successfully prepared a hierarchically porous ZIF-67 (H-ZIF-67) by incorporating the polyvinylpyrrolidone (PVP) at room temperature. Compared to standard control ZIF-67 (C-ZIF-67) with a yield of 81% and a BET specific surface area of 1228 m²·g⁻¹, the H-ZIF-67 not only exhibited improved crystallinity and pore structure but also achieved a yield of up to 93% and a BET specific surface area of 1457 m²·g⁻¹. Due to its hierarchically porous structure, H-ZIF-67 demonstrated excellent adsorption capacity and efficiency for methylene orange (MO). Additionally, the composite separator created by combining H-ZIF-67 with nanocellulose (CNF) exhibited remarkable uniformity and dispersion in zinc batteries. In comparison to a conventional CNF separator, the porous structure and high specific surface area of H-ZIF-67 significantly enhanced its electrolyte wettability and Zn²⁺ transport rates. Its abundant Lewis acid sites effectively promoted the uniform deposition of Zn²⁺, thereby suppressing the formation of zinc dendrites and improving the cycling and safety performance of zinc-ion batteries. Experimental results indicate that the ion conductivity of the membrane was 4.31 mS·cm⁻¹, the electrolyte absorption rate was 316%, and it could cycle stable for over 4000 h at a current density of 1 mA·cm⁻² with a discharge capacity of 1 mAh·cm⁻². This achievement will open up new avenues for the preparation and application of ZIF-67 composite separators in aqueous zinc-ion batteries.

Keywords:

ZIF-67; battery separator; zinc-ion battery

1. Introduction

Metal–organic frameworks (MOFs) are three-dimensional inorganic–organic hybrid materials formed via coordination bonds between metal ions and organic ligands [1]. ZIF-67 (3D-[Co-(mim)₂]·2H₂O, mim = 2-Methylimidazolate) belongs to the class of Zeolitic Imidazolate Frameworks (ZIFs) that are MOF materials that can be synthesized through the room temperature solution synthesis method [2]. It boasts excellent thermal stability and controllable pore sizes, characterized by a dodecahedral crystal structure [3]. ZIF-67 and its derivatives have been extensively developed and studied across various application fields due to their highly stable structural characteristics, including gas adsorption and separation [4], sensing [5], catalysis [6], and catalysis [7].

Currently, the synthesis methods for ZIF-67 primarily include hydrothermal synthesis [8], solvothermal synthesis [9], and microwave-assisted synthesis [10]. Each method has its distinct advantages and application scenarios. Among these, hydrothermal synthesis is a commonly employed MOF synthesis technique that promotes the crystallization of precursors in a closed-reaction vessel under higher temperature and high (autogenous) pressure conditions [11]. Due to its ability to yield high-quality crystals under still relatively mild conditions, this method is widely adopted for synthesizing ZIF-67. Qiang et al. [12] grew ZIF-67 crystals in situ on a substrate and studied their adsorption performance for methylene orange (MO) dye. The results indicated that ZIF-67 achieved an adsorption capacity of up to 130.2 mg·g⁻¹ (pH = 2) for MO dye. Chao et al. [13] reported the synthesis of a porous composite material from ZIF-67 and layered double hydroxide (LDH) for the removal of MO. This product demonstrated a better adsorption capacity for methyl orange of 180.5 mg·g⁻¹ (pH = 2), but its mechanical strength was limited, making it prone to fracture under mechanical stress. Although hydrothermal synthesis has advantages such as operational ease, high crystal quality, and uniform pore structure [14], its development is constrained by high temperature and pressure conditions, relatively high energy consumption, long reaction time (typically several hours to several days), and low efficiency [15].

Zinc-ion batteries, noted for their high safety [16], high volumetric energy density [17], and low cost [18], are garnering increasing attention from researchers. Compared to lithium-ion batteries, zinc-ion batteries have a higher electrolyte ignition point and superior safety characteristics [19], while their electrolyte–ion conductivity is nearly two orders of magnitude higher [20], making them a potential substitute for next-generation energy storage systems. However, to fully harness the performance of zinc-ion batteries, the comprehensive performance of the separator is crucial. The performance of the separator is influenced by various factors such as pore size, pore distribution, porosity, wettability, electrolyte absorption, ion conductivity, mechanical strength, thermal stability, and electrochemical stability [21]. To improve the performance of zinc-ion batteries, it is essential to develop separators with excellent mechanical properties, thermal stability, and electrochemical stability [22].

Huang et al. [23] directly modified bacterial cellulose (BC) nanofibers with ZIF-67 through in situ growth to prepare BC/ZIF-67 composite separators for lithium-ion batteries. The addition of ZIF-67 helps to prevent the aggregation of nanofibers and enhances electrolyte retention capacity, which promotes ion transport. However, the influence of ZIF-67 on the aggregation of BC nanofibers and the formation of hydrogen bonds between fibers not only reduces the mechanical properties of the separator but may also affect its electrochemical performance and ion transport efficiency [24]. Chen et al. [25] coated ZIF-67 directly onto the positive electrode material using blade coating technology, thereby replacing traditional polypropylene (PP) separators. The highly porous structure of the ZIF-67 particles may facilitate ion diffusion. Consequently, separators based on ZIF-67 exhibit higher porosity, ionic conductivity, and better thermal stability compared to PP separators. At present, research reports on cellulose nanofibers (CNF) and ZIF-67 composite materials in zinc-ion separators indicate that this composite can effectively enhance the performance of zinc-ion batteries [26]. Tu et al. [27] prepared a material using nanomaterialization and functionalization strategies (Zn-CNF@XG), but the ion conductivity was only 1.85 × 10⁻² mS·cm⁻¹. Yang et al. [28] developed a multifunctional separator composed of nanocellulose (Zr-CNF) coated with Zr⁴⁺ hydrolysis products via the in situ hydrolysis of Zr⁴⁺, but the assembled battery exhibited a cycle time of only 680 h. Thus, the composite material of nanocellulose and ZIF-67 presents significant potential for improving the performance of zinc-ion batteries, particularly in enhancing ion conductivity, increasing separator stability, and promoting uniform metal deposition [29].

Polyvinylpyrrolidone (PVP) was used as a template agent to fabricated hierarchically porous MOF [30]. Here, we present a novel approach to synthesize a hierarchically porous ZIF-67 utilizing PVP, significantly enhancing its structural characteristics, such as specific surface area and pore volume. The hierarchically porous H-ZIF-67 demonstrates superior performance in dye adsorption and showcases its potential in zinc-ion batteries by being integrated into CNF to create an efficient separator.

2. Experimental Part

2.1. Materials

Cellulose nanoscale (CNF) (solid content 1.6%, purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., Shanghai, China), cobalt hexahydrate and chloride (CoCl₂·6H₂O, AR, 99%, purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., Shanghai, China), 2-methylimidazole (Hmim, C₄H₆N₂, AR, 98%, purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., Shanghai, China), polyvinylpyrrolidone (PVP, (Mw = 24,000, K23-27) purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., Shanghai, China), and other chemical reagents were all analytically pure and did not require further treatment.

2.2. Material Preparation

2.2.1. Preparation of ZIF-67

C-ZIF-67 (Control ZIF-67): CoCl₂·6H₂O (0.237 g) and Hmim (0.328 g) were separately dissolved in 10 mL of deionized water and stirred for 30 min. Then, we combined the two solutions and continued stirring for 6 h. After stirring for 6 h, we centrifuged the mixture at 9000 r·min⁻¹ for 10 min. We discarded the supernatant, washed the sediment with 20 mL of methanol, and sonicated it for 20 min. We repeated these steps three times to fully remove any unreacted starting materials. Finally, we dried the product under a vacuum at 80 °C for 12 h to eliminate any residual solvent molecules and obtained the final product as a purple powder (yield 0.1806 g, 81%).

H-ZIF-67 (Hierarchically porous ZIF-67): We dissolved CoCl₂·6H₂O (0.237 g), Hmim (0.328 g), and PVP (100 mg) separately in 10 mL of deionized water and stirred for 30 min. Then, we combined the two solutions and stirred for 6 h. After stirring, we centrifuged the mixture at 9000 r·min⁻¹ for 10 min. We discarded the supernatant and washed the sediment with 20 mL of methanol to remove excess PVP. After washing, we sonicated it for 20 min, repeating the previous steps three times to ensure the complete removal of any unreacted starting materials. Finally, we dried the product under a vacuum at 80 °C for 12 h to eliminate any residual solvent molecules and obtain the final product as a purple powder (yield 0.2074 g, 93%).

2.2.2. Preparation of H-ZIF-67/CNF Membrane

First, we stirred 9.3125 g of CNF aqueous dispersion with 150 mL of anhydrous ethanol for 12 h. Then, we centrifuged the mixture and wash it three times, after centrifugation dispersion in anhydrous ethanol (120 mL) for later use. Next, we added the previously prepared H-ZIF-67 (223 mg) to the CNF dispersion (120 mL) to obtain a suspension of H-ZIF-67/CNF. We ultrasonically dispersed the suspension using an ultrasonic cleaning machine (Shenzhen Fangao Microelectronics Co., Ltd., Shenzhen, China) for 1 h, then filtered it into a wet film through simple vacuum filtration. Finally, we dried the wet film in an oven at 80 °C for 6 h. Once dried, we made it into a 17 mm × 17 mm separator for battery assembly.

2.3. Characterization Methods

2.3.1. Characterization of Material

A ZEISS Sigma 300 scanning electron microscope (SEM) (Carl Zeiss AG, Oberkochen, Germany) was employed to observe the morphology of the surface of the material and separator samples at various magnifications (acceleration voltage is 3–5 kV). A Bruker D8 Advance powder X-ray diffractometer (Bruker, Karlsruhe, Germany) was used to characterize the crystallinity and crystal structure through the intensity and position of the diffraction peaks of the material and the composite separator (using a Cu target and a K α radiation (λ = 1.54182 nm) light source). The specific surface area and pore structure of ZIF-67 were analyzed using a Quantachrome Autosorb IQ MP (Quantachrome Instruments Inc., Boynton Beach, FL, USA), a fully automated specific surface area and porosity analyzer.

2.3.2. Battery Testing

CR2025-type coin cells were assembled at room temperature under air atmosphere. All the materials required for assembly were ultrasonically cleaned with anhydrous ethanol and dried in an oven at 80 °C before use. The structure of the cell, from top to bottom, was as follows: negative shell, spacer, negative electrode material, electrolyte, separator, positive electrode material, and positive shell.

Using a 3 mol·L⁻¹ ZnSO₄ aqueous solution as the electrolyte and zinc foil as the symmetrical electrode, the coin cell was assembled with a separator measuring 17 mm in diameter. Tests were conducted to evaluate the ionic conductivity, the AC impedance, the ionic migration number, the symmetrical battery rate performance, and the symmetrical battery cycle performance.

Ionic conductivity calculation [31]:

To calculate the ionic conductivity, the CNF separator and H-ZIF-67/CNF separator were assembled with two stainless steel electrodes using a 3 mol·L⁻¹ ZnSO₄ solution as the electrolyte, forming a stainless-steel symmetrical battery. Electrochemical impedance spectroscopy (EIS) was performed on both of the types of separator samples assembled in the batteries using a CHI760e electrochemical workstation, under the conditions of a frequency range of 10⁴ to 10⁻² Hz and an amplitude of 10 mV. The impedance values for both the CNF separator and the H-ZIF-67/CNF separator were then substituted into Formula (1) to calculate the ion conductivity of the membrane (in mS·m⁻¹):

σ = \frac{L}{A R}

(1)

In the formula:

L = thickness of the diaphragm sample (m);
A = area of the stainless-steel sheet (cm²);
R = impedance value of the diaphragm (Ω).

2.4. Study on the Storage and Transport Rate of Cationic Dyes

Ten milligrams of the prepared ZIF-67 sample were added as an adsorbent to 20 mL of a cationic dye solution with an initial mass concentration of 150 mg·L⁻¹. The prepared cationic dye solution was placed in an ultrasonic cleaner and sonicated for 10 min. After standing for 5 min, the supernatant was taken, and its absorbance was measured using a UV spectrophotometer (Shimadzu Instrument Co., Ltd., Shimadzu, Japan) until equilibrium was reached.

3. Results and Discussion

3.1. Structural Control and Performance Study of ZIF-67

Figure 1a shows the structural diagram of ZIF-67. 2-Methylimidazolate ligands bridge between individual cobalt atoms and span the edges of the cuboctahedral β-cage in the sodalite network.

Figure 1b presents a comparison of the powder X-ray diffraction (PXRD) patterns for C-ZIF-67, H-ZIF-67, and simulated ZIF-67. It is evident that the characteristic peaks of C-ZIF-67 and H-ZIF-67 perfectly aligned with those of the simulated ZIF-67, indicating that both synthesized C-ZIF-67 and H-ZIF-67 are phase-pure ZIF-67.

Figure 1c,d shows the SEM images of C-ZIF-67 and H-ZIF-67. It can be observed that both ZIF-67 samples exhibit a regular dodecahedral morphology, which is a typical characteristic of ZIF-67 particles. Compared to C-ZIF-67, the particle morphology of H-ZIF-67 is more uniform, and the size of the composite particles can be controlled successfully. This enhancement may be attributed to the addition of PVP, which improved the nucleation of ZIF-67 and resulted in a more uniform structure.

Figure 2a presents the N₂ adsorption/desorption isotherms of C-ZIF-67 and H-ZIF-67, with specific surface areas of 1228 m²·g⁻¹ and 1457 m²·g⁻¹, respectively. It is evident that H-ZIF-67 exhibits a significant hysteresis loop for N₂ adsorption and desorption within the range of 0.8 < P/P₀ < 1, while C-ZIF-67 does not show any hysteresis loop, indicating that H-ZIF-67 possesses mesoporous characteristics. The pore size distribution curves, obtained by fitting the data using the linear density functional theory (NLDFT) model, are shown in Figure 2b and further confirm the presence of mesopores in H-ZIF-67. PVP is a polymer that has garnered significant attention for its versatile applications, particularly as a nucleating, coordination, and template agent, which could produce hierarchical porous MOF [30]. In our case, the addition of PVP played a similar role, which affected the formation of ZIF-67 crystals, resulting in the formation of mesopores in H-ZIF-67.

Figure 2c illustrates the time-dependent adsorption curves for the uptake of methylene orange (MO) by C-ZIF-67 and H-ZIF-67. This graph depicts the relationship between the adsorption amount and time of H-ZIF-67 in a 150 mg·L⁻¹ MO solution. As the adsorption time increased from 0 to 80 min, the uptake of H-ZIF-67 for MO rapidly rose from 0 mg·g⁻¹ to 260 mg·g⁻¹. After 80 min, the rate of MO adsorption by H-ZIF-67 gradually decreased, indicating that the adsorption capacity was approaching saturation and the adsorption and transport of ions remained relatively constant. This suggests that the adsorption capacity of MO by H-ZIF-67 was significantly higher than that of C-ZIF-67.

Figure 2d displays the maximum adsorption capacity for MO of both C-ZIF-67 and H-ZIF-67. It is clear that H-ZIF-67 demonstrates a maximum adsorption capacity of 286 mg·g⁻¹ for MO, which is ~50% higher than that of C-ZIF-67.

3.2. Application of H-ZIF-67 in the Separator of Zinc-Ion Batteries

3.2.1. Characterization of H-ZIF-67/CNF Zinc-Ion Battery Separator

We firstly prepared the H-ZIF-67/CNF separator using a room temperature blending method. In Figure 3a,b, the morphology of the CNF separator is shown in a SEM image, where fibers are tightly interlaced and stacked, resulting in pores, reduced interlayer spacing between fibers, and decreased pore volume. This arrangement can affect the deposition of Zn²⁺ in zinc-ion batteries, leading to rapid zinc dendrite growth and a decrease in cycling performance.

Figure 3c,d show SEM images of the H-ZIF-67/CNF separator. It can be observed that granular ZIF-67 particles were present in the composite separator, and the fiber arrangement was more dispersed with larger pores. This indicates that the addition of H-ZIF-67 significantly improved the stacking condition of the separator and increased its pore size. Moreover, due to ZIF-67’s excellent ionic conductivity, it can enhance the ion transport of zinc ions in the H-ZIF-67/CNF separator and reduce the AC impedance.

Figure 3e,f illustrate the contact angles of the CNF separator and the H-ZIF-67/CNF separator (using the 3 mol·L⁻¹ ZnSO₄ solution). The contact angle of the CNF separator was 34°, whereas the H-ZIF-67/CNF separator had a contact angle of only 20°. The significant decrease in contact angle indicates that the H-ZIF-67/CNF separator exhibited superior electrolyte wettability, enhancing its interaction with the electrolyte.

Figure 3g presents the PXRD patterns of H-ZIF-67 and the H-ZIF-67/CNF separator. The characteristic diffraction peaks of the H-ZIF-67/CNF separator were generally consistent with those in the H-ZIF-67 pattern, indicating that H-ZIF-67 had been successfully incorporated into the CNF matrix without structural damage, which is crucial for maintaining the material’s functionality.

Figure 3h shows the stress–strain curves of the CNF separator and the H-ZIF-67/CNF separator. It can be seen that the tensile strength of the H-ZIF-67/CNF separator was 0.9 MPa, which was significantly lower than the tensile strength of the CNF separator at 1.6 MPa, but still higher than that of commonly used glass fiber (GF) zinc-ion battery separators [33,34,35]. Additionally, the thickness of the H-ZIF-67/CNF separator was 14 μm, meeting the current requirements for thickness reduction and good mechanical strength in zinc-ion battery separators [36,37].

From the porosity of the CNF separator, the C-ZIF-67/CNF separator, and the H-ZIF-67/CNF separator displayed in Figure 3i, it can be observed that the porosity of the CNF separator was 63.5%, the C-ZIF-67/CNF separator was 76.5%, while that of the H-ZIF-67/CNF separator was 94.9%. This enhancement in porosity is attributed to the addition of H-ZIF-67, rather than the coating alone. The addition of H-ZIF-67 improved the accumulation of cellulose and significantly increased the porosity of the H-ZIF-67/CNF separator.

Figure 3j shows the electrolyte adsorption rates of the CNF separator, C-ZIF-67/CNF separator, and the H-ZIF-67/CNF separator, which are 164%, 215% and 316%, respectively. This indicates that the addition of H-ZIF-67 can significantly enhance the electrolyte adsorption of the separator, as H-ZIF-67 improved both wettability and electrolyte retention.

3.2.2. Electrochemical Performance Analysis

Figure 4a illustrates the body impedance of the CNF separator and the H-ZIF-67/CNF separator. The body impedance of the H-ZIF-67/CNF separator (0.86 Ω) was significantly lower than that of the CNF separator (1.63 Ω), indicating reduced resistance to zinc ion transmission, which enhanced the flow of zinc ions.

Figure 4b presents the ion conductivity data for the CNF separator and the H-ZIF-67/CNF separator. The sample impedance data obtained was substituted into ion conductivity calculation Formula (1), revealing that the ion conductivities of the CNF separator and the H-ZIF-67/CNF separator were 0.57 S·m⁻¹ and 4.31 S·m⁻¹, respectively. The ionic conductivity of the H-ZIF-67/CNF separator had been significantly improved, likely due to the rich porous structure provided by H-ZIF-67, which facilitated rapid ion conduction. Therefore, it can be inferred that the use of the H-ZIF-67/CNF separator can extend the life of the battery separator and enhance the overall performance of the battery.

Figure 4c displays the AC impedance spectra of the CNF separator and the H-ZIF-67/CNF separator. It is apparent that the impedance value of the H-ZIF-67/CNF separator (140 Ω) was much lower than that of the CNF separator (395 Ω), resulting in a smaller semicircle diameter in the low-frequency region, which corresponds to lower charge transfer impedance. Consequently, utilizing the H-ZIF-67/CNF separator as a zinc-ion battery separator was advantageous for ensuring uniform zinc deposition and can improve the cycling performance of zinc-ion batteries.

3.2.3. Electrochemical Performance Testing of Zinc Symmetric Batteries

As shown in Figure 5a, at different current densities (0.2 mA·cm⁻², 0.2 mAh·cm⁻²; 0.5 mA·cm⁻², 0.5 mAh·cm⁻²; 1 mA·cm⁻², 1 mAh·cm⁻²; 2 mA·cm⁻², 2 mAh·cm⁻²; 5 mA·cm⁻², 5 mAh·cm⁻²; 0.5 mA·cm⁻², 0.5 mAh·cm⁻²), the H-ZIF-67/CNF separator exhibited a more stable voltage–time curve and lower polarization voltage throughout the current density range. In contrast, the CNF separator performed well under low-current densities but it had difficulty adapting to high-current densities, resulting in poorer stability. The high specific surface area and pore structure of H-ZIF-67 not only enhanced the ion transport efficiency but also provided buffer space to mediate the current fluctuations, reducing voltage fluctuations and polarization.

Figure 5b indicates that under the conditions of 2 mA·cm⁻² and 2 mAh·cm⁻², the overpotential of the H-ZIF-67/CNF separator was lower, and its cycling stability was better. This further confirms the effectiveness of H-ZIF-67 in reducing polarization and improving ion conductivity.

Figure 5c shows that under the conditions of 1 mA·cm⁻² and 1 mAh·cm⁻², the H-ZIF-67/CNF separator remained stable during the 4000 h test without any short circuits.

Thus, the H-ZIF-67/CNF separator significantly improved the long-term stability and safety of the battery, demonstrating broad application prospects.

4. Conclusions

This article describes the synthesis of ZIF-67 with a hierarchical pore structure at room temperature by incorporating polyvinylpyrrolidone (PVP). H-ZIF-67 exhibits an excellent pore volume and BET specific surface area. Due to its hierarchical pore structure, H-ZIF-67 demonstrates a larger adsorption capacity and rate for the dye molecule methylene orange compared to traditional ZIF-67.

Subsequently, we successfully prepared the H-ZIF-67/CNF separator at room temperature through co-mixing and suction filtration. H-ZIF-67 possesses a high specific surface area, abundant Lewis acid sites, a rich pore structure, and an appropriate pore size, all of which significantly enhance the ion transport capacity of the H-ZIF-67/CNF separator and improve both the electrolyte absorption rate and charge carrier transport capacity. Its ionic conductivity is measured at 4.31 mS·cm⁻¹, with an electrolyte absorption rate of 316%.

In addition, compared to the CNF separator, the H-ZIF-67/CNF separator significantly reduces polarization voltage, AC impedance, and activation energy. The Zn/Zn symmetric battery assembled using this separator demonstrates a long cycle life of over 4000 h. More importantly, our room temperature synthesis avoids the need for high-temperature and high-pressure processes, thereby reducing energy consumption and production costs. This simplifies the manufacturing process and makes it suitable for large-scale production. As a result, this straightforward procedure enhances the competitiveness of the H-ZIF-67/CNF separator in industrial applications and provides new avenues for developing high-performance cobalt-based MOF aqueous zinc-ion battery separators.

Author Contributions

Conceptualization, T.Z. and Y.C.; methodology, J.Y.; validation, J.Y., P.X. and S.N.; formal analysis, J.Y. and S.P.; investigation, S.P., J.C. and F.L.; resources, T.Z., C.J. and Y.C.; writing—original draft preparation, T.Z.; writing—review and editing, T.Z., C.J. and Y.C.; supervision, T.Z., C.J. and Y.C.; funding acquisition, T.Z. and Y.C. All authors have read and agreed to the published version of the manuscript.

Funding

The work was supported by the National Natural Science Foundation of China (52073086, 51802094), the Natural Science Foundation of Hunan Province (2024JJ7164, 2023JJ60447), the Postgraduate Scientific Research Innovation Project of Hunan Province (CX20240908) and Scientific research and innovation Foundation of Hunan University of Technology (CX2413).

Data Availability Statement

All relevant data are within the paper.

Conflicts of Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

References

Bakar, B.; Dik, G.; Ulu, A.; Ateş, B. Immobilization of Xylanase into Zeolitic Imidazolate Framework-67 (ZIF-67) and Manganese-Doped ZIF-67 (Mn/ZIF-67): A Comparison Study. Top. Catal. 2024, 67, 698–713. [Google Scholar] [CrossRef]
Park, H.; Amaranatha Reddy, D.; Kim, Y.; Ma, R.; Choi, J.; Kim, T.K.; Lee, K.-S. Zeolitic imidazolate framework-67 (ZIF-67) rhombic dodecahedrons as full-spectrum light harvesting photocatalyst for environmental remediation. Solid State Sci. 2016, 62, 82–89. [Google Scholar] [CrossRef]
Zhong, G.; Liu, D.; Zhang, J. The application of ZIF-67 and its derivatives: Adsorption, separation, electrochemistry and catalysts. J. Mater. Chem. A 2018, 6, 1887–1899. [Google Scholar] [CrossRef]
Sun, X.; Zhou, N.; Liu, M. Adsorption desulfurization over porous carbons derived from ZIF-67 and AC. J. Solid State Chem. 2023, 322, 123985. [Google Scholar] [CrossRef]
Wang, Y.-X.; Tsao, P.-K.; Rinawati, M.; Chen, K.-J.; Chen, K.-Y.; Chang, C.Y.; Yeh, M.-H. Designing ZIF-67 derived NiCo layered double hydroxides with 3D hierarchical structure for Enzyme-free electrochemical lactate monitoring in human sweat. Chem. Eng. J. 2022, 427, 131687. [Google Scholar] [CrossRef]
Gong, H.; Sun, G.; Shi, W.; Li, D.; Zheng, X.; Shi, H.; Liang, X.; Yang, R.; Yuan, C. Nano-Au-decorated hierarchical porous cobalt sulfide derived from ZIF-67 toward optimized oxygen evolution catalysis: Important roles of microstructures and electronic modulation. Carbon Energy 2024, 6, e432. [Google Scholar] [CrossRef]
Zhang, Q.; Zhi, P.; Zhang, J.; Duan, S.; Yao, X.; Liu, S.; Sun, Z.; Jun, S.C.; Zhao, N.; Dai, L.; et al. Engineering Covalent Organic Frameworks Toward Advanced Zinc-Based Batteries. Adv. Mater. 2024, 36, 2313152. [Google Scholar] [CrossRef] [PubMed]
Qian, J.; Sun, F.; Qin, L. Hydrothermal synthesis of zeolitic imidazolate framework-67 (ZIF-67) nanocrystals. Mater. Lett. 2012, 82, 220–223. [Google Scholar] [CrossRef]
Ethiraj, J.; Palla, S.; Reinsch, H. Insights into high pressure gas adsorption properties of ZIF-67: Experimental and theoretical studies. Microporous Mesoporous Mater. 2020, 294, 109867. [Google Scholar] [CrossRef]
Campos, R.D.; Menezes de Oliveira, A.L.; Rostas, A.M.; Kuncser, A.C.; Negrila, C.C.; Galca, A.-C.; Félix, C.; Castellano, L.; da Silva, F.F.; dos Santos, I.M.G. TiO₂/ZIF-67 nanocomposites synthesized by the microwave-assisted solvothermal method: A correlation between the synthesis conditions and antimicrobial properties. New J. Chem. 2023, 47, 2177–2188. [Google Scholar] [CrossRef]
Zhao, H.; Qu, Z.-R.; Ye, H.-Y.; Xiong, R.-G. In situ hydrothermal synthesis of tetrazole coordination polymers with interesting physical properties. Chem. Soc. Rev. 2008, 37, 84–100. [Google Scholar] [CrossRef] [PubMed]
Qiang, T.; Wang, S.; Wang, Z.; Ren, L. Recyclable 3D konjac glucomannan/graphene oxide aerogel loaded with ZIF-67 for comprehensive adsorption of methylene blue and methyl orange. J. Ind. Eng. Chem. 2022, 116, 371–384. [Google Scholar] [CrossRef]
Nazir, M.A.; Khan, N.A.; Cheng, C.; Shah, S.S.A.; Najam, T.; Arshad, M.; Sharif, A.; Akhtar, S.; Rehman, A.U. Surface induced growth of ZIF-67 at Co-layered double hydroxide: Removal of methylene blue and methyl orange from water. Appl. Clay Sci. 2020, 190, 105564. [Google Scholar] [CrossRef]
Shi, W.; Song, S.; Zhang, H. Hydrothermal synthetic strategies of inorganic semiconducting nanostructures. Chem. Soc. Rev. 2013, 42, 5714–5743. [Google Scholar] [CrossRef]
Al Obeidli, A.; Ben Salah, H.; Al Murisi, M.; Sabouni, R. Recent advancements in MOFs synthesis and their green applications. Int. J. Hydrogen Energy 2022, 47, 2561–2593. [Google Scholar] [CrossRef]
Zhu, C.; Li, P.; Xu, G.; Cheng, H.; Gao, G. Recent progress and challenges of Zn anode modification materials in aqueous Zn-ion batteries. Coord. Chem. Rev. 2023, 485, 215142. [Google Scholar] [CrossRef]
Wang, Z.; Hu, J.; Han, L.; Wang, Z.; Wang, H.; Zhao, Q.; Liu, J.; Pan, F. A MOF-based single-ion Zn²⁺ solid electrolyte leading to dendrite-free rechargeable Zn batteries. Nano Energy 2019, 56, 92–99. [Google Scholar] [CrossRef]
Liang, Y.; Dong, H.; Aurbach, D.; Yao, Y. Current status and future directions of multivalent metal-ion batteries. Nat. Energy 2020, 5, 646–656. [Google Scholar] [CrossRef]
Haregewoin, A.M.; Wotango, A.S.; Hwang, B.-J. Electrolyte additives for lithium ion battery electrodes: Progress and perspectives. Energy Environ. Sci. 2016, 9, 1955–1988. [Google Scholar] [CrossRef]
Al-Amin, M.; Islam, S.; Shibly, S.U.; Iffat, S. Comparative Review on the Aqueous Zinc-Ion Batteries (AZIBs) and Flexible Zinc-Ion Batteries (FZIBs). Nanomaterials 2022, 12, 3997. [Google Scholar] [CrossRef]
Li, B.; Zeng, Y.; Zhang, W.; Lu, B.; Yang, Q.; Zhou, J.; He, Z. Separator designs for aqueous zinc-ion batteries. Sci. Bull. 2024, 69, 688–703. [Google Scholar] [CrossRef] [PubMed]
Li, L.; Jia, S.; Cheng, Z.; Zhang, C. Improved Strategies for Separators in Zinc-Ion Batteries. ChemSusChem 2023, 16, e202202330. [Google Scholar] [CrossRef] [PubMed]
Huang, Q.; Zhao, C.; Li, X. Enhanced electrolyte retention capability of separator for lithium-ion battery constructed by decorating ZIF-67 on bacterial cellulose nanofiber. Cellulose 2021, 28, 3097–3112. [Google Scholar] [CrossRef]
Li, D.; Tian, X.; Wang, Z.; Guan, Z.; Li, X.; Qiao, H.; Ke, H.; Luo, L.; Wei, Q. Multifunctional adsorbent based on metal-organic framework modified bacterial cellulose/chitosan composite aerogel for high efficient removal of heavy metal ion and organic pollutant. Chem. Eng. J. 2020, 383, 123127. [Google Scholar] [CrossRef]
Chen, P.; Shen, J.; Wang, T.; Dai, M.; Si, C.; Xie, J.; Li, M.; Cong, X.; Sun, X. Zeolitic imidazolate framework-67 based separator for enhanced high thermal stability of lithium ion battery. J. Power Sources 2018, 400, 325–332. [Google Scholar] [CrossRef]
Guo, S.; Zhang, P.; Feng, Y.; Wang, Z.; Li, X.; Yao, J. Rational design of interlaced Co9S8/carbon composites from ZIF-67/cellulose nanofibers for enhanced lithium storage. J. Alloys Compd. 2020, 818, 152911. [Google Scholar] [CrossRef]
Tu, W.-B.; Liang, S.; Song, L.-N.; Wang, X.-X.; Ji, G.-J.; Xu, J.-J. Nanoengineered Functional Cellulose Ionic Conductor Toward High- Performance All-Solid-State Zinc-Ion Battery. Adv. Funct. Mater. 2024, 34, 2316137. [Google Scholar] [CrossRef]
Yang, S.; Zhang, Y.; Zhang, Y.; Deng, J.; Chen, N.; Xie, S.; Ma, Y.; Wang, Z. Designing Anti-Swelling Nanocellulose Separators with Stable and Fast Ion Transport Channels for Efficient Aqueous Zinc-Ion Batteries. Adv. Funct. Mater. 2023, 33, 2304280. [Google Scholar] [CrossRef]
Wang, L.; Xu, S.; Song, Z.; Jiang, W.; Zhang, S.; Jian, X.; Hu, F. Promoting uniform lithium deposition with Janus gel polymer electrolytes enabling stable lithium metal batteries. InfoMat 2024, 6, e12551. [Google Scholar] [CrossRef]
Wang, Y.; Yang, C.; Zhang, C.; Duan, M.; Wang, H.; Fan, H.; Li, Y.; Shangguan, J.; Lin, J. Effect of hierarchical porous MOF-199 regulated by PVP on their ambient desulfurization performance. Fuel 2022, 319, 123845. [Google Scholar] [CrossRef]
Zhang, Y.-J. Entropy and ionic conductivity. Phys. A Stat. Mech. Its Appl. 2012, 391, 4470–4475. [Google Scholar] [CrossRef]
Kwon, H.T.; Jeong, H.-K.; Lee, A.S.; An, H.S.; Lee, J.S. Heteroepitaxially Grown Zeolitic Imidazolate Framework Membranes with Unprecedented Propylene/Propane Separation Performances. J. Am. Chem. Soc. 2015, 137, 12304–12311. [Google Scholar] [CrossRef] [PubMed]
Lei, Y.; Li, Q.; Liu, Q.; Zeng, Y.; Li, J.; Huang, W.; Wang, F.; Zhong, S.; Yan, D. Low-cost separator with dust-free fabric composite cellulose acetate toward stable dendrite-free aqueous zinc-ion batteries. Chem. Eng. J. 2024, 479, 147846. [Google Scholar] [CrossRef]
Wu, F.; Du, F.; Ruan, P.; Cai, G.; Chen, Y.; Yin, X.; Ma, L.; Yin, R.; Shi, W.; Liu, W.; et al. Regulating zinc deposition behaviors by using a functional PANI modification layer on a separator for high performance aqueous zinc-ion batteries. J. Mater. Chem. A 2023, 11, 11254–11263. [Google Scholar] [CrossRef]
Zhang, Y.; Liu, Z.; Li, X.; Fan, L.; Shuai, Y.; Zhang, N. Loosening Zinc Ions from Separator Boosts Stable Zn Plating/Striping Behavior for Aqueous Zinc Ion Batteries. Adv. Energy Mater. 2023, 13, 2302126. [Google Scholar] [CrossRef]
Liu, Z.; Dong, Y.; Qi, X.; Wang, R.; Zhu, Z.; Yan, C.; Jiao, X.; Li, S.; Qie, L.; Li, J.; et al. Stretchable separator/current collector composite for superior battery safety. Energy Environ. Sci. 2022, 15, 5313–5323. [Google Scholar] [CrossRef]
Lee, J.; Lee, H.; Bak, C.; Hong, Y.; Joung, D.; Ko, J.B.; Lee, Y.M.; Kim, C. Enhancing Hydrophilicity of Thick Electrodes for High Energy Density Aqueous Batteries. Nano-Micro Lett. 2023, 15, 97. [Google Scholar] [CrossRef]

Figure 1. (a) The structural diagram of ZIF-67; (b) PXRD patterns of C-ZIF-67 and H-ZIF-67 compared to simulated ZIF-67 (from deposited cif file 1429244 [32]); SEM images of (c) C-ZIF-67; and (d) H-ZIF-67 (the magnification of the SEM images is 1 × 10⁵).

Figure 2. (a) N₂ adsorption/desorption isotherms of C-ZIF-67 and H-ZIF-67 (the adsorption-filled symbols are solid, the desorption empty symbols are hollow). (b) DFT pore size distribution curves of C-ZIF-67 and H-ZIF-67 (density functional theory, DFT). (c) Time-dependent adsorption curves of C-ZIF-67 and H-ZIF-67 for MO. (d) Uptake of MO by C-ZIF-67 and H-ZIF-67.

Figure 3. SEM images of CNF separator (a,b) (the magnification of SEM images is 2 × 10⁴); SEM images of H-ZIF-67/CNF separator (c,d) (the magnification of SEM image C is 2 × 10⁴, and the magnification of SEM image D is 1 × 10⁴); (e) CNF separator contact angle diagram; (f) H-ZIF-67/CNF separator contact angle diagram; (g) PXRD patterns of H-ZIF-67 and H-ZIF-67/CNF separator; (h) stress–strain curves of CNF separator and H-ZIF-67/CNF separator; (i) porosity of CNF separator, C-ZIF-67/CNF separator and H-ZIF-67/CNF separator; (j) electrolyte adsorption graphs of CNF separator, C-ZIF-67/CNF separator and H-ZIF-67/CNF separator.

Figure 4. (a) Nyquist plot of SS//SS cell with CNF separator and H-ZIF-67/CNF separator; (b) ion conductivity diagram of CNF cell and H-ZIF-67/CNF cell with Zinc Symmetric Battery separator; (c) Nyquist plot of Zn//Zn cell with CNF separator and H-ZIF-67/CNF separator.

Figure 5. (a) Voltage–time curves of Zn//Zn symmetric cells with CNF separator and H-ZIF-67/CNF separator at different current densities; (b) voltage–time curves of Zn//Zn symmetric cells with CNF separator and H-ZIF-67/CNF separator at 2 mA·cm⁻² and 2 mAh·cm⁻²; (c) voltage–time curves of Zn//Zn symmetric cells with CNF separator and H-ZIF-67/CNF separator at 1 mA·cm⁻² and 1 mAh·cm⁻².

Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.

© 2024 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).

Share and Cite

MDPI and ACS Style

Zhao, T.; Yu, J.; Xiao, P.; Nie, S.; Peng, S.; Chen, J.; Luo, F.; Janiak, C.; Chen, Y. Preparation of Hierarchical Porous ZIF-67 and Its Application in Zinc Battery Separator. Chemistry 2024, 6, 1363-1373. https://doi.org/10.3390/chemistry6060080

AMA Style

Zhao T, Yu J, Xiao P, Nie S, Peng S, Chen J, Luo F, Janiak C, Chen Y. Preparation of Hierarchical Porous ZIF-67 and Its Application in Zinc Battery Separator. Chemistry. 2024; 6(6):1363-1373. https://doi.org/10.3390/chemistry6060080

Chicago/Turabian Style

Zhao, Tian, Jiangrong Yu, Pengcheng Xiao, Saiqun Nie, Shilin Peng, Jiayao Chen, Fuli Luo, Christoph Janiak, and Yi Chen. 2024. "Preparation of Hierarchical Porous ZIF-67 and Its Application in Zinc Battery Separator" Chemistry 6, no. 6: 1363-1373. https://doi.org/10.3390/chemistry6060080

APA Style

Zhao, T., Yu, J., Xiao, P., Nie, S., Peng, S., Chen, J., Luo, F., Janiak, C., & Chen, Y. (2024). Preparation of Hierarchical Porous ZIF-67 and Its Application in Zinc Battery Separator. Chemistry, 6(6), 1363-1373. https://doi.org/10.3390/chemistry6060080

Article Menu