Introduction

Energy band engineering

Z-scheme overall water splitting

Strategies for photocatalytic hydrogen generation activity improvement

Conclusions

References

Abstract

Bismuth-based composite oxides are always considered the best visible-light photocatalysts for oxygen production. However, they are failed to photocatalytic reduce the hydrogen from water, due to their lower conduction band made up by Bi 6p and O 2p. Thus, it is significant to modulate their levels of the conduction and valence bands satisfying the redox potential for both H+/H2 and O2/H2O, which will directly lead to discovering new visible-light materials for photocatalytic hydrogen generation. Recent years, some modified bismuth-based composite oxides have been reported to achieve photocatalytic hydrogen production. In this paper, a review of photocatalytic hydrogen generation by bismuth-based composite oxides is presented, mainly including energy band engineering, Z-scheme overall water splitting, and strategies for photocatalytic activity improvement.

Introduction

Photocatalytic hydrogen generation from pure water, known as the “holy grail” in chemistry, can convert solar energy directly into green storable chemical energy [1,2]. After decades of development, solar-to-hydrogen energy conversion efficiency has exceeded 1% [3]. However, it is still far from the practical application requirement of at least 10% solar energy conversion efficiency. Thus, photocatalytic hydrogen generation is still in the experimental research stage. Discovering new materials (especially visible-light photocatalysts) and improving solar energy conversion efficiency are still two major themes in research.