Recent developments in dark photocatalytic hydrogen production over smart catalysts

Abstract

Widespread application of solar-driven hydrogen production is hampered by two major challenges: the safety risks associated with high-pressure H₂ storage and transport, and the intermittent nature of solar energy. Inspired by the natural spatial and temporal separation of light and dark reactions in photosynthesis, the emerging strategy of dark photocatalysis aims to separate the collection and conversion of solar energy. In the past few years, encouraging progress has been made in the dark photocatalytic production of hydrogen. Therefore, we summarize the advances in this field over the past few years. This review first discusses various charge storage mechanisms in depth. Then, a comprehensive review of key material systems is conducted, covering carbon-nitrogen-based materials, metal–organic frameworks, polyoxometalate-based materials, two-dimensional layered materials, as well as heterojunction/interface engineering and the combination of semiconductors with polyoxometalates. Furthermore, the performance of photo-charging and dark hydrogen evolution is analyzed in detail. Finally, we look forward to the future development direction of this field. This review aims to offer valuable insights and guidance for the design of efficient and stable dark photocatalytic materials.

Keywords

Dark photocatalytic hydrogen production / photoinduced charge separation / electron storage / persistent catalysis / semiconductor

Acknowledgements

Doubao and DeepSeek were employed during manuscript preparation, solely for language polishing to improve the fluency of the text. The authors take full responsibility for the integrity, originality, and accuracy of the work.

Authors contribution

Ding Y: Conceptualization, supervision, writing-review & editing. Dong X: Writing-original draft. Zhou Y, Fang X: Writing-review & editing.

Conflicts of interest

The authors declare no conflicts of interest.

Ethical approval

Not applicable.

Consent to participate

Not applicable.

Consent for publication

Not applicable.

Availability of data and materials

Not applicable.

Funding

This work was supported by the National Natural Science Foundation of China (Grant Nos. 22472071, 22075119 and 12404325), the Natural Science Foundation of Gansu Province (Grant No. 21JR7RA440), the Lanzhou Municipal-Level Science and Technology Reserve Project (Grant No. 2025-3-015), and the Fundamental Research Funds for the Central Universities (Grant Nos. lzujbky-2024-it49 and lzujbky-2024-it05).

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