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Electrochromic (EC) materials allow for dynamic tuning of optical properties via an applied electric field, presenting great potential in energy-efficient technologies, such as smart windows for effective light and temperature regulation. The precise control of precursor concentration has proven to be a powerful approach in tailoring the physicochemical properties of semiconducting metal oxides. In this study, we employed a one-step electrodeposition technique to fabricate tungsten oxide (WO3) thin films, systematically exploring how varying precursor concentrations influence the material's characteristics. X-ray diffraction analysis revealed significant changes in diffraction patterns, reflecting subtle structural modifications due to concentration variations. Additionally, scanning electron microscopy revealed significant changes in the microstructure, showing a progression from small nanogranules to larger agglomerations within the film matrix. The W-25 mM thin film delivered exceptional EC performance, efficiently accommodating lithium ions while showcasing superior EC properties. The optimized electrode, denoted as W-25 mM, showcased exceptional EC metrics, featuring the highest optical modulation at 82.66%, outstanding reversibility at 99%, and a notably high coloring efficiency of 83.01 cm2/C. These findings emphasize the importance of precursor concentration optimization in enhancing the EC properties of WO3 thin films, contributing to the advancement of high-performance, energy-efficient materials. [ABSTRACT FROM AUTHOR]

As modern civilization's energy demands continue to rise, the need for efficient renewable energy solutions becomes increasingly critical. In addressing this challenge, our research explores the potential of newly developed iron (Fe)-doped molybdenum disulfide (MoS2) thin-film electrodes, synthesized through a simple hydrothermal method, as a promising energy storage device. By systematically varying the Fe doping levels, we aim to elucidate the relationship between Fe content and the structural, morphological, and electrochemical properties of the MoS2 electrodes. The optimized FM-3 electrode exhibited a remarkable areal capacitance of 8.25 F/cm2 at a current density of 10 mA/cm2 with an energy density of 0.22 mWh/cm2 and a power density of 2.2 mW/cm2. Furthermore, the FM-3 demonstrated impressive long-term cycling stability, retaining 85.58% of its initial capacitance after 10,000 charge–discharge cycles. To further explore practical applicability, an asymmetric pouch-type supercapacitor device was assembled using an FM-3 electrode and activated carbon. The device achieved an impressive areal capacitance of 0.43 F/cm2 at a current density of 20 mA/cm2, delivering an energy density of 0.133 mWh/cm2 and a power density of 7.5 mW/cm2. The exceptional performance of the FM-3 electrode can be attributed to the enhanced diffusion rate, charge transfer efficiency, and better carrier mobility induced by Fe doping. This work not only highlights the significant electrochemical performance improvements of Fe-doped MoS2 electrodes but also demonstrates their potential for scalable energy storage solutions, making a valuable contribution to the field of next-generation energy storage technologies. [ABSTRACT FROM AUTHOR]

Electrochromic materials enable the precise control of their optical properties, making them essential for energy-saving applications such as smart windows. This study focuses on the synthesis of molybdenum-doped niobium oxide (Mo-Nb2O5) thin films using a one-step hydrothermal method to investigate the effect of Mo doping on the material's electrochromic performance. Mo incorporation led to distinct morphological changes and a transition from a compact granular structure to an anisotropic rod-like feature. Notably, the MN-3 (0.3% Mo) sample displayed an optimal electrochromic performance, achieving 77% optical modulation at 600 nm, a near-perfect reversibility of 99%, and a high coloration efficiency of 89 cm2/C. Additionally, MN-3 exhibited excellent cycling stability, with only 0.8% degradation over 5000 s. The MN-3 device also displayed impressive control over color switching, underscoring its potential for practical applications. These results highlight the significant impact of Mo doping on improving the structural and electrochromic properties of Nb2O5 thin films, offering improved ion intercalation and charge transport. This study underscores the potential of Mo-Nb2O5 for practical applications in energy-efficient technologies. [ABSTRACT FROM AUTHOR]

In this work, Ni3V2O8 (NVO) and Ni3V2O8-reduced graphene oxide (NVO-rGO) are synthesized hydrothermally, and their extensive structural, morphological, and electrochemical characterizations follow subsequently. The synthetic materials' crystalline structure was confirmed by X-ray diffraction (XRD), and its unique marigold-like morphology was observed by field emission scanning electron microscopy (FESEM). The chemical states of the elements were investigated via X-ray photoelectron spectroscopy (XPS). Electrochemical impedance spectroscopy (EIS), Galvanostatic charge–discharge (GCD), and cyclic voltammetry (CV) were used to assess the electrochemical performance. A specific capacitance of 132 F/g, an energy density of 5.04 Wh/kg, and a power density of 187 W/kg were demonstrated by Ni3V2O8-rGO. Key electrochemical characteristics were b = 0.67; a transfer coefficient of 0.52; a standard rate constant of 6.07 × 10−5 cm/S; a diffusion coefficient of 5.27 × 10−8 cm2/S; and a series resistance of 1.65 Ω. By employing Ni3V2O8-rGO and activated carbon, an asymmetric supercapacitor with a specific capacitance of 7.85 F/g, an energy density of 3.52 Wh/kg, and a power density of 225 W/kg was achieved. The series resistance increased from 4.27 Ω to 6.63 Ω during cyclic stability tests, which showed 99% columbic efficiency and 87% energy retention. The potential of Ni3V2O8-rGO as a high-performance electrode material for supercapacitors is highlighted by these findings. [ABSTRACT FROM AUTHOR]

Electrochromic materials allow for precise control of their optical properties by applying an electric field, which has led to recent developments in energy-saving and indoor temperature control systems like smart windows. The selective incorporation of metal dopants is an effective technique for generating highly advanced semiconducting metal oxides with precisely customized physicochemical characteristics. In this report, we employed a one-step electrodeposition process to fabricate nickel-doped tungsten oxide (W–Ni) thin films, systematically probing the impact of nickel (Ni) doping on the collective material characteristics. Comprehensive X-ray diffraction research revealed significant changes in diffraction patterns, suggesting slight modifications in the structure caused by Ni doping. The scanning electron microscopy showed complex differences in the microstructure of the film, such as a dense surface, porosity, and clustering of nanogranules. The WNi-3% thin film doped at 3 wt. % exhibited excellent electrochromic performance by efficiently handling lithium ions and displaying favorable electrochromic properties. The improved electrode, WNi-3%, showed a maximum optical modulation of 81.90%, exceptional reversibility of 99.4%, and a high coloration efficiency of 75.12 cm2/C. These findings underscore the efficacy of Ni-doping in tailoring the electrochromic properties of nickel-doped tungsten oxide thin films, thereby advancing the frontiers of high-performance electrochromic materials for energy-efficient applications. [ABSTRACT FROM AUTHOR]

Previous studies examined the incorporation of several transition metal oxides into niobium oxide (Nb 2 O 5) to enhance the electrochromic (EC) performance. The objective was to improve the durability, color neutrality, coloring efficiency, and optical characteristics because individual metal oxides often exhibit limits that might affect overall functioning. Therefore, an innovative approach, integrating mixed metal oxides, emerges. This novel approach addresses these challenges and unlocks new possibilities to enhance EC efficiency. This paper introduces a new method for synthesizing niobium oxide/tungsten oxide (Nb 2 O 5 /WO 3) bilayer composite materials using a combination of facile hydrothermal synthesis with electrodeposition. The electrochromic, structural, morphological, and optical characteristics of Nb 2 O 5 thin films were enhanced by conducting thorough investigations into different electrodeposition cycles of WO 3. X-ray diffraction confirmed the amorphous nature of WO 3 in combination with the crystalline orthorhombic Nb 2 O 5 structure. Raman spectroscopy examined the vibrational modes and structural attributes in the Nb 2 O 5 /WO 3 bilayer composite thin films. X-ray photoelectron spectroscopy was conducted to examine the chemical composition, elemental state, and surface characteristics. Field emission scanning electron microscopy was used to examine the impact of different WO 3 electrodeposition cycles on the morphology of Nb 2 O 5 thin films, revealing the formation of porous, clumped, and dense nanogranules on the film surface. EC investigations highlight the superior performance of the NW-20 thin film, showing efficient Li+ accommodation. The optimized NW-20 sample exhibits excellent EC performance, including high optical modulation (81.48 %), good reversibility (98.11 %), and high coloration efficiency (115.09 cm2/C) with long-term cycling stability. The NW-20 electrode incorporated into a device form exhibited functionality on a real-world scale, delivering remarkable EC performance with substantial optical modulation (78.1 %) and excellent cycling stability. These findings expand the potential applications of Nb 2 O 5 /WO 3 bilayer composite materials for EC performance. [Display omitted] • Nb2O 5 /WO 3 bilayer films synthesized via hydrothermal and electrodeposition techniques. • NW-20 displayed superior electrochromic traits among others (NW-15 and NW-25). • Increase in the transmittance modulation leads to an increase in the CE. • NW-20 exhibits notable electrochromic stability with only 1.4 % loss over 3000s. [ABSTRACT FROM AUTHOR]

In this present article, we have reported a simple and cost-effective ex-situ synthesis of TiO2-ZnO (TZ) nanocomposite thin film by utilizing sol-gel, hydrothermal and solid-state reaction methods. The Ag/TZ/FTO nanocomposite device was developed and demonstrated the bipolar resistive switching (RS) characteristics for resistive memory applications. The result of XRD analysis confirms that the nanocomposite has mixed tetragonal and hexagonal crystal structures of TiO2 and ZnO, respectively. The hysteresis loop is an essential criterion for recognizing memristive devices and similar characteristic was noticed for the developed nanocomposite device. Besides, basic memristive properties were calculated from the I-V data. The charge transportation of Ag/TZ/FTO nanocomposite device takes place because of Ohmic and space charge limited current. The collective effect of oxygen vacancies and Ag ions was a basis of RS effect in the Ag/TZ/FTO nanocomposite device. [ABSTRACT FROM AUTHOR]