Mechanistic Insights into Photocatalytic WO₃ for Hydrogen Generation

Abstract

Growing environmental concerns and the limitations of fossil fuel resources have recently led to increased focus on clean and renewable energy sources. Hydrogen (H₂) has gained importance as an alternative clean fuel with its potential to become the primary chemical energy carrier. Photocatalytic hydrogen generation offers a capable solution to the energy crisis and has gained significant attention as a renewable energy solution, offering independence from fossil fuels and zero carbon dioxide emissions. Tungsten oxide (WO₃) offers to be a promising photocatalyst for Hydrogen Evolution Reaction (HER) with its ability to tune the band gap, robust absorption in the visible spectrum range, steadiness in harsh reaction conditions, low cost, and reduced toxicity. Various synthetic methods can be employed to fabricate photocatalysts with diverse morphologies, sizes, and structures, all of which significantly influence their catalytic performance to varying extents. This review goals to explicitly highlight and discourse the main properties of WO₃ and its modifications for photocatalytic HER via different synthesis methods. Modification in WO₃ to its corresponding composites, heterojunctions are explicitly explained in this review.

Keywords

Photocatalysts / HER / WO₃ / Band gap / Quantum yield / Composites

Acknowledgments

The authors acknowledge University of Cincinnati for providing research infrastructure.

Author Contributions

P.C.M.: Original draft, Writing—review and editing. B.M.—Review and editing. P.G.S.: Supervision, review and editing.

Ethics Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

The data used in the review can be accessed through the cited publication within the manuscript.

Funding

This research received no external funding.

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.

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