Search Results (828)

Flexibility, light weight, and mechanical robustness are the key advantages of flexible photovoltaic (PV) modules, making them highly versatile for sustainable energy solutions. Unlike traditional rigid PV modules, their flexible nature makes them incredibly versatile for harnessing energy in places where doing so was once impossible. They have a wide range of applications due to their flexibility and moldability, making it possible to conform these modules to surfaces like curved rooftops and other irregular structures. In this paper, we provide a comprehensive review of all the materials used in flexible PV modules with a focus on their role in sustainability. We thoroughly discuss the active-layer materials for crystalline silicon (c-Si)-based solar cells (SC) and thin-film solar cells such as cadmium telluride (CdTe), as well as copper indium gallium diselenide (CIGS), amorphous thin-film silicon (a-Si), perovskite and organic solar cells. Various properties, such as the optical, barrier, thermal, and mechanical properties of different substrate materials, are reviewed. Transport layers and conductive electrode materials are discussed with a focus on emerging trends and contributions to sustainable PV technology. Various fabrication techniques involved in making flexible PV modules, along with advantages, disadvantages, and future trends, are highlighted in the paper. The commercialization of flexible PV is also discussed, which is a crucial milestone in advancing and adapting new technologies in the PV industry with a focus on contributing toward sustainability. Full article

We present structural, morphological, optical and photocatalytic properties of multiferroic Bi_0.98Ba_0.02FeO₃ (BBFO2) perovskite thin films prepared by a combined sol–gel and spin-coating method. X-ray diffraction (XRD) analysis revealed that all the perovskite films consisted of the stable polycrystalline rhombohedral phase structure (space group R3c) with a tolerance factor of 0.892. By using Rietveld refinement of diffractogram XRD data, crystallographic parameters, such as bond angle, bond length, atom position, unit cell parameters, and electron density measurements were computed. Scanning electron microscopy (SEM) allowed us to assess the homogeneous and smooth surface morphology of the films with a small degree of porosity, while chemical surface composition characterization by X-ray photoelectron spectroscopy (XPS) showed the presence of Bi, Fe, O and the doping element Ba. Absorption measurements allowed us to determine the energy band gap of the films, while photoluminescence measurements have shown the presence of oxygen vacancies, which are responsible for the enhanced photocatalytic activity of the material. Photocatalytic degradation experiments of Methylene Blue (MB), Methyl orange (MO), orange G (OG), Violet and Rhodamine B (RhB) performed on top of BBFO2 thin films under solar light showed the degradation of all pollutants in varying discoloration efficiencies, ranging from 81% (RhB) to 54% (OG), 53% (Violet), 47% (MO) and 43% (MB). Full article

Bismuth-based perovskite derivatives, (CH₃NH₃)₃Bi₂I₉ (MBI), are promising non-toxic light-absorbing materials widely used in various photoelectric devices because of their excellent stability. However, MBI-based perovskite solar cells (PSCs) are limited by poor film quality, and the performance of such a device is far behind that of lead-based PSCs. In this work, the crystal structure and morphological properties of MBI films were compared across different preparation methods. The two-step vapor-assisted method can prepare continuous dense MBI films because MBI crystal nucleation is induced by the BiI₃ seed layer. The MBI film grown by this method is better for the production of excellent PSCs compared to the film prepared by the solution method. The best photovoltaic device based on the MBI film could obtain a power conversion efficiency of 1.13%. An MBI device is stored in the glove box for 60 days, and the device’s performance is maintained at 99%. These results indicate that the vapor-assisted deposition of MBI films can be an effective method to improve the performance of bismuth-based planar PSCs. Full article

Organic–inorganic lead halide perovskite solar cells (PSCs) have presented promising improvements within recent years due to the superior photophysical properties of perovskites. The efficiency of PSCs is closely related to the quality of the of the perovskite film. Additive engineering is an effective strategy to regulate the crystallization of perovskite film. Therefore, in this work, we introduce methylammounium chloride (MACl) into a perovskite precursor as an additive to improve the crystallization of perovskite film and to suppress the formation of defects to achieve high-performance PSCs. By meticulously investigating and studying the influence of different percentages of MACl additives on perovskite film quality, we obtain that the best amount of incorporated MACl is 10%. Thanks the employment of the optimal amount of MACl, the perovskite film shows a significantly improved morphology with larger grains, a smoother surface, and suppressed defects. Finally, the target PSCs with the addition of 10% MACl present the highest PCE of 23.61%, which is much higher than the value (16.72%) of the control device. Full article

This article aims to complete a review of current literature describing the measurement and characterization of photoelectric and geometric properties of perovskite solar cell (PSC) film layer materials using the spectroscopic ellipsometry (SE) measurement technique. Firstly, the influence of film quality on the performance of PSCs is combed and analyzed. Secondly, SE measurement technology is systematically introduced, including the measurement principle and data analysis. Thirdly, a detailed summary is provided regarding the characterization of the geometric and optoelectronic properties of the substrate, electron transport layer (ETL), perovskite layer, hole transport layer (HTL), and metal electrode layer using SE. The oscillator models commonly used in fitting film layer materials in PSCs are comprehensively summarized. Fourthly, the application of SE combined with various measurement techniques to assess the properties of film layer materials in PSCs is presented. Finally, the noteworthy direction of SE measurement technology in the development of PSCs is discussed. The review serves as a valuable reference for further enhancing the application of SE in PSCs, ultimately contributing to the commercialization of PSCs. Full article

In the present work, nine ‘defect’ perovskites with the chemical formula A₂ZrX₆ have been studied, where the A-site cations are a methylammonium cation, formamidinium cation, and trimethyl-sulfonium cation and the X-site anions are halogen, X = Cl, Br, and I. We employ periodic DFT calculations using GGA-PBE, MBJ, HSEsol, and HSE06 functionals. All studied compounds exhibit a wide-bandgap energy that ranges from 5.22 eV to 2.11 eV, while for some cases, geometry optimization led to significant structural modification. It was found that the increase in the halogen size resulted in a decrease in the bandgap energy. The choice of the organic A-site cation affects the bandgap as well, which is minimal for the methylammonium cation. Such semiconductors with organic cations may be utilized in optoelectronic devices, given the substantial benefit of solution processability and thin film formation compared to purely inorganic analogs, such as Cs₂ZrX₆. Full article

Two-dimensional tin halide perovskites are of significant interest for light emitting applications. Here, we investigate the effect of organic cation A on the stability of different Dion–Jacobson tin-based halide perovskites. The ASnBr₄ materials using diammonium cation A with shorter alkyl chains are found to exhibit improved stability, exhibiting dramatic stability difference between the most stable HDASnBr₄, where HDA denotes 1,6-hexanediammonium, and two materials with 8- and 10-carbon alkyl chain ammonium cations. The HDASnBr₄ powders were thermally stable at 100 °C in an argon environment but exhibited decreasing photoluminescence with time in ambient air at 100 °C. The sample degradation at 100 °C is accelerated compared to room temperature, but it proceeds along similar pathways, namely phase transformation followed by perovskite decomposition. Light emission from HDASnBr₄ thin films could be further enhanced by methanol vapor treatment, and warm white emission with Commission Internationale de l’Eclairage (CIE) coordinates (0.37, 0.34) could be obtained by combining HDASnBr₄ with a blue-emitting polymer film, while direct mixing of blue phosphor and HDASnBr₄ powder yields white emission with CIE coordinates of (0.34, 0.32). Full article

Perovskite solar cells (PSCs) have emerged as a promising photovoltaic technology, yet their stability under environmental stressors remains a critical challenge. This study examines the substrate-dependent degradation mechanisms of perovskite films and evaluates the role of methylammonium chloride (MACl) incorporation. Devices fabricated on ITO and glass substrates exhibited markedly different stability behaviors under high-humidity conditions. ITO substrates delayed the phase transition from the black α-phase to the yellow δ-phase due to stronger substrate–film interactions and reduced defect densities, while glass substrates facilitated rapid degradation through moisture infiltration and grain boundary instability. MACl incorporation enhanced the initial crystallinity and optoelectronic properties of the perovskite films, as evidenced by superior power conversion efficiency and photon absorption. However, residual MACl under humid conditions introduced structural instability, particularly on glass substrates. To address these challenges, a fully coated ITO structure, referred to as the Island Type design, was proposed. This structure eliminates exposed glass regions, leveraging the stabilizing properties of ITO to suppress moisture infiltration and prolong device durability. The findings provide a comprehensive understanding of the interplay between substrate properties and material composition in PSC stability and highlight the potential of structural optimizations to balance efficiency and durability for commercial applications. Full article

Water pollution caused by emerging contaminants is increasing due to rising urbanization, industrialization, and agriculture production; therefore, new materials with high efficiency for wastewater decontamination are needed. A perovskite material based on 1% Ag-doped LaMnO₃ synthesized through a sol–gel technique was combined with PVP in a 1:10 (w/w) ratio and subjected to different temperature and microwave conditions at various time intervals. The composite materials were obtained as thin films (S1, S2) or powders (S3) and were analyzed by modern techniques. The SEM analysis showed strongly agglomerated, asymmetric formations for the S1, S2 materials; as for the S3 composite, irregularly shaped grains of perovskite were deposited on the polymer surface. Small, round formations across the surface, mainly organized as clusters with conic/square-shaped particles and observed asperity on top, were highlighted by AFM images. The XRD spectra confirmed the presence of both the perovskite and PVP phases, and the crystallite size of the materials was determined to be in the range of 33–43 nm. The structural analyses, FT-IR, and Raman spectroscopy proved the interactions between the perovskite and the polymer, which led to novel composite materials. The different methods used for the synthesis of the new materials influenced their features and behavior. Moreover, the composites were successfully tested for methyl orange (MO) elimination from an acidic aqueous solution in dark conditions, with fast and complete (>95%) MO degradation at pH = 2. Full article

Memristors are promising candidates for next-generation non-volatile memory devices, offering low power consumption and high-speed switching capabilities. However, conventional metal oxide-based memristors are constrained by fabrication complexity and high costs, limiting their commercial viability. Organic–inorganic hybrid perovskites (OIHPs), known for their facile solution processability and unique ionic–electronic conductivity, provide an attractive alternative. This study presents a conjugated polyelectrolyte (CPE), PhNa-1T, as an interlayer for OIHP memristors to enhance the high-resistance state (HRS) performance. A post-treatment process using n-octylammonium bromide (OABr) was further applied to optimize the interlayer properties. Devices treated with PhNa-1T/OABr achieved a significantly improved ON/OFF ratio of 2150, compared to 197 for untreated devices. Systematic characterization revealed that OABr treatment improved film morphology, reduced crystallite strain, and optimized energy level alignment, thereby reinforcing the Schottky barrier and minimizing current leakage. These findings highlight the potential of tailored interlayer engineering to improve OIHP-based memristor performance, offering promising prospects for applications in non-volatile memory technologies. Full article

Perovskite solar cells are part of the third generation of solar cells, a technology that holds the potential to reduce the use of fossil fuels in energy production. Some factors, such as stability and toxicity, jeopardize the scaling process towards commercialization and access to worldwide markets. This work comprises a review over the last decade on PSC advances and progress in the most highly cited databases. A marked trend was found in replacing Pb for Sn from the absorbing perovskite materials, as well as finding the transport layers that will help in the stability and the efficiency of the solar cell. WO₃ is presented as a viable element for the formation of the electron transport layer. Spiro-OMeTAD is the most used compound for the hole transport layer, but other viable substitutes were also found. Lastly, the Cs₂SnI₆ double perovskite was identified as one of the most stable perovskites that emerged in these 10 years. The efficiency and stability of Sn-based solar cells is still very low when compared to their Pb-based counterparts, driving the current research in material science to enhance their performance. Full article

Abstract: Quantum dot–polymer composites have the advantages of high luminescent quantum yield (PLQY), narrow emission half-peak full width (FWHM), and tunable emission spectra, and have broad application prospects in display and lighting fields. Research on quantum dots embedded in polymer films and plates has made great progress in both synthesis technology and optical properties. However, due to the shortcomings of quantum dots, such as cadmium selenide (CdSe), indium phosphide (InP), lead halide perovskite (LHP), poor water, oxygen, and light stability, and incapacity for large-scale synthesis, their practical application is still restricted. Various polymers, such as methyl methacrylate (PMMA), polyethylene terephthalate (PET), polystyrene (PS), polyvinylidene fluoride (PVDF), polypropylene (PP), etc., are widely used in packaging quantum dot materials because of their high plasticity, simple curing, high chemical stability, and good compatibility with quantum dot materials. This paper focuses on the application and development of quantum dot–polymer materials in the field of backlight displays, summarizes and expounds the synthesis strategies, advantages, and disadvantages of different quantum dot–polymer materials, provides inspiration for the optimization of quantum dot–polymer materials, and promotes their application in the field of wide-color-gamut backlight display. Full article

Hole-doped manganese oxides exhibit a gigantic negative magnetoresistance, referred to as colossal magnetoresistance (CMR), owing to the interplay between double-exchange (DE) ferromagnetic metal and charge-ordered antiferromagnetic insulator/semiconductor phases. Magnetoresistive manganites display a sharp resistivity drop at the metal–insulator transition temperature (T^MI). CMR effects in perovskite manganites, specifically La_0.67Ca_0.33MnO₃ (La-Ca-Mn-O or LCMO), have been extensively investigated. This review paper provides a comprehensive introduction to the crystallographic structure, as well as the electronic and magnetic properties, of LCMO films. Furthermore, we delve into a detailed discussion of the effects of epitaxial strain induced by different substrates on LCMO films. Additionally, we review the early findings and diverse applications of LCMO thin films. Finally, we outline potential challenges and prospects for achieving superior LCMO film properties. Full article

A crucial problem of the photoinduced degradation of perovskite semiconductors based on complex lead halides has been addressed here by suppressing PbI₂ photolysis to metallic lead. The systematic screening of >30 modifying cations introduced as substituents for 5% of Pb²⁺ in the PbI₂ composition has revealed their tremendous effects on the rate of material degradation under light exposure. Thus, the most successful stabilizing cations could maintain a high absorbance of the Pb_0.95M_0.1/nI₂ films and block Pb⁰ formation after 400 h of continuous illumination, when the non-modified PbI₂ films completely decomposed to Pb⁰ and I₂. The obtained results present a promising solution for the problem of metallic lead formation in the active layer of perovskite solar cells during their operation, which can pave the way for the development of a new generation of highly efficient and stable perovskite photovoltaics. Full article

Flexible perovskite solar cells (F-PSCs) have the advantages of high power-per-weight, solution processability, and bending durability and have emerged as a competitive photovoltaic technology for various applications. As the core electron transport layer (ETL) in n-i-p-type device configurations, the solution-processed SnO₂ generally suffers from serious defect stacking on films, compromising the charge transport properties and the performance of resulting devices. Herein, we proposed a media-filling strategy to optimize the contact quality at the buried interface by introducing Al₂O₃ nanoparticles on the SnO₂ surface. Rather than forming a compact insulating layer, the Al₂O₃ can fill the grain boundaries of SnO₂ and smooth the substrate surface. Optimized interfacial contact under careful concentration control can rationally minimize the contact area of the perovskite with the surface imperfections of SnO₂ to mitigate trap-assisted charge recombination. Furthermore, the reduced surface roughness of SnO₂ facilitates the uniform deposition and oriented growth of upper perovskite film. As a result, the target F-PSCs achieved an impressive efficiency of 23.83% and retained 80% of the initial performance after 5000 bending cycles at a radius of four mm. Full article