The substitutional doping of tungsten oxide (WO₃) with metal ions demonstrates a promising approach to enhance its photoelectrochemical (PEC) water splitting efficiency. In this article, the substitutional doping of Sn ions into WO₃ lattice and its effect on optical, electrical, band edge, and PEC water splitting properties are explored. Sn-doped WO₃ thin films were synthesized using a facile hydrothermal method. The characterization data reveal that the doping of Sn alters the morphology, induces multiple crystal phases, effects the crystal orientation, reduces the band gap, and increases the carrier density of WO₃. With the uniform distribution of Sn ions in WO₃ and the decreased charge transfer resistance at the electrode/electrolyte interface, the doped WO₃ show notable enhancement in its PEC activity compared to the undoped WO₃. The band edge study revealed that the introduction of Sn in WO₃ lattice causes an increase in the energy distance between the valence band edge and Fermi level and, at the same time, induces a downward shift in both the valence and conduction band edges towards higher potentials with respect to reversible hydrogen electrode (RHE). Conclusively, this work shows significant and new insights about Sn-doped WO₃ photoanodes and their influence on PEC water splitting efficiency.

Water electrolysis coupled with renewable energy is one of the principal methods for producing green hydrogen (or renewable hydrogen). Among the different electrolysis technologies, the evolving anion exchange membrane water electrolysis (AEMWE) shows the utmost promise for the manufacture of green hydrogen in an inexpensive way. In the present review, we highlight the most current and noteworthy achievements of AEMWE, which include the advancements in increasing the polymer anionic conductivity, understanding the mechanism of degradation of AEM, and the design of the electrocatalyst. The important issues affecting the AEMWE behaviour are highlighted, and future constraints and openings are also discussed. Furthermore, this review provides strategies for producing dynamic and robust AEMWE electrocatalysts.

It is imperative to transition towards sustainable energy sources to mitigate the escalating threat of global warming and ameliorate the adverse impacts of climatic changes.