RESEARCH PROGRESS OF Z-SCHEME HETEROJUNCTION PHOTOCATALYTIC SYSTEMS FOR CO2 REDUCTION

Abstract

Abstract: Z-scheme heterojunctions separate photogenerated electrons and holes to different semiconductors, featuring broad spectrum response, high charge separation efficiency, strong redox capacity as well as high stability. Z-scheme heterojunctions have emerged as a powerful material to catalyze CO₂ reduction reaction (CO₂RR) and have attracted much research effort in the field of photocatalysis. The recent research progress on Z-scheme photocatalytic systems for CO₂ reduction is reviewed. Different charge transfer mechanisms in three types of Z-scheme heterojunctions (liquid-phase, all-solid-state and direct Z-scheme) are elaborated. Relative merits of different Z-scheme heterojunctions and their applications in CO₂RR are summarized. It is pointed out that in the future, more effort needs be devoted to investigate the generation mechanisms of photocatalytic CO₂RR products (especially C₂ and C₂+ products), to elucidate the charge transfer mechanisms in photocatalytic Z-scheme heterojunctions, to trace back to the origin of CO₂RR products, to improve experimental design and evaluation, and to conduct systematic researches for large-scale industrial trials.

Key words: Z-scheme heterojunction, photocatalysis, CO₂ reduction, semiconductor, charge transfer

References

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