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This study investigates the implications of Sr doping upon the photoelectrochemical (PEC) water-splitting efficiency of WO 3 , utilizing both experimental and theoretical approaches. Sr-doped WO 3 films were synthesized hydrothermally. An extensive analysis was conducted to analyze the crystal structures, band edge, morphologies, band edge, electrochemical, and optical characteristics of Sr-doped films. The PEC investigations demonstrated that the Sr-doped WO 3 photoanode achieved a 3.6-fold enhanced photocurrent density of 1.62 mAcm -2 (at 1.23 V vs. RHE). Moreover, a maximum photocurrent density of 5.25 mAcm -2 was yielded in tartaric acid electrolyte. Incorporating Sr into the WO 3 lattice increased charge carrier density by lowering charge transfer resistance, leading to efficient charge separation, diffusion, and transfer properties. Remarkable photoconversion and charge separation efficiency values of 0.369 % and 79.8 % were obtained for Sr-doped WO 3 , respectively. Additionally, adding a hole scavenger observed a recorded photocurrent density value of 3.64 mAcm -2 . A stoichiometric evolution (2:1) of H 2 /O 2 gases with exceptional Faradaic efficiency of over 90 % was obtained after the Sr doping in WO 3 . In addition, density functional theory (DFT) calculations indicated an alteration to the bandgap and density of states, consistent with the experimental results, suggesting beneficial transformation for both the surface/bulk characteristics of WO 3 following Sr incorporation., Competing Interests: Declaration of competing 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., (Copyright © 2025 Elsevier Inc. All rights reserved.)

In this study, the impact of lead (Pb) doping on the photoelectrochemical (PEC) water splitting performance of tungsten oxide (WO 3 ) photoanodes was investigated through a combination of experimental and theoretical approaches. Pb-doped WO 3 nanostructured thin films were synthesized hydrothermally, and extensive characterizations were conducted to study their morphologies, band edge, optical and photoelectrochemical properties. Pb-doped WO 3 exhibited efficient carrier density and charge separations by reducing the charge transfer resistance. The 0.96 at% Pb doping shows a record photocurrent of ∼ 1.49 mAcm -2 and ∼ 3.44 mAcm -2 (with the hole scavenger) at 1.23 V vs. RHE besides yielding a high charge separation and Faradaic efficiencies of ∼ 86 % and > 90 %, respectively. A shift in the Fermi level towards the conduction band was also observed upon the Pb doping. Additionally, density functional theory (DFT) simulations demonstrated the changes in the density of states and bandgap upon Pb doping, exhibiting favorable changes in the surface and bulk properties of WO 3 ., Competing Interests: Declaration of competing 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., (Copyright © 2024 Elsevier Inc. All rights reserved.)

The phase control of transition metal dichalcogenides (TMDs) is an intriguing approach for tuning the electronic structure toward extensive applications. In this study, WSe 2 nanosheets synthesized via a colloidal reaction exhibit a phase conversion from semiconducting 2H to metallic 2M under Se-rich growth conditions (i.e., increasing the concentration of Se precursor or lowering the growth temperature). High-resolution scanning transmission electron microscopy images are used to identify the stacking sequence of the 2M phase, which is distinctive from that of the 1T' phase. First-principles calculations employing various Se-rich models (intercalation and substitution) indicated that Se enrichment induces conversion to the 2M phase. The 2M phase WSe 2 nanosheets with the Se excess exhibited enhanced electrocatalytic performance in the hydrogen evolution reaction (HER). In situ X-ray absorption fine structure studies suggested that the excess Se atoms in the 2M phase WSe 2 enhanced the HER catalytic activity, which is supported by the Gibbs free energy (ΔG H* ) of H adsorption and the Fermi abundance function. These results provide an appealing strategy for phase control of TMD catalysts., (© 2023 Wiley-VCH GmbH.)

The development of a single junction photoelectrode material having specific properties is essential and challenging for the efficient application in solar water splitting for oxygen production and a high value-added product, hydrogen. Moreover, the present material solutions based on binary metal oxides offer limited catalytic activity and hydrogen production efficiency. Therefore, it is paramount to develop and exploit a unique range of materials derived from ternary metal oxides with specifically engineered properties to advance in photoelectrochemical (PEC) water splitting. Among the ternary oxides, copper vanadates offer promising characteristics, such as a narrow bandgap and catalytic surface properties along with favorable band edges for facile oxygen evolution reaction (OER), which is considered the bottleneck step in performing overall water dissociation. Furthermore, the copper vanadates allow the tuning of the stoichiometry through which a wide range of polymorphs and materials could be obtained. This review provides a complete outlook on the range of copper vanadates and the established synthesis approach, morphology, crystal structure, band edge properties, and PEC characterizations. Mainly, the underlying charge dynamic properties, carrier path length, effect of doping, and influence of surface catalysts are discussed. The review concludes that the advancement toward obtaining low-bandgap materials is a main challenge to overcome the limitations for efficient water dissociation to OER and copper vanadates, which offer a promising solution with their unique properties and advantages. Importantly, intense and strategically focused research is vital to overcome the scientific challenges involved in copper vanadates and to explore and exploit new polymorphs to set new efficiency benchmarks and PEC water splitting solutions.

High-performing electrolytes at low operating temperatures have become an inevitable trend in the development of low-temperature solid oxide fuel cells (LT-SOFCs). Such electrolytes have drawn significant attention due to their appeal for high performance. Herein, we propose a new material by doping Y 3+ into Gd 2 O 3 for LT-SOFC electrolyte use. The prepared material was characterized in terms of crystal structure, surface, and interface properties, followed by its application in LT-SOFCs. YDG delivered promising SOFC performance with a power density of 1046 mW cm -2 at 550 °C along with high ionic conductivity of 0.19 S cm -1 . Moreover, impedance spectra revealed that YDG exhibited the least ohmic resistance of 0.06-0.09 Ω cm 2 at 550-460 °C. Furthermore, stable operation for 60 h demonstrated the chemical stability of the material in reduced temperature environments. Density function theory was also applied to analyze the electronic band structure and density of states of the synthesized sample. Our findings thus certify that YDG as a high-performing electrolyte at low operating temperatures.