Abstract: The research development of novel photocatalysts is the core issue of photo-driven CO₂ conversion into high value-added chemicals or fuels, which should be of important significance for achieving the goal of “carbon peak and carbon neutralization”. In this paper, a series of novel Bi-Y-O photocatalyst systems were synthesized by EDTA-assisted hydrothermal method, and with the change of EDTA amount, the crystal structures of as-prepared samples are variational. BiYO₃ crystal is obtained with 0.4 g EDTA addition or without EDTA, while Bi_1.46Y_0.54O₃ and Bi₃YO₆ crystals are synthesized with 0.8 g and 1.2 g EDTA addition, respectively. The photocatalytic CO₂ reduction tests reveal that as-prepared BiYO₃ with 0.4 g EDTA addition exhibits the best CO₂ photoreduction activity, and CO yield is 18.29 μmol·g^-1·h^-1. After three cycle tests, CO yield still reaches 17.32 μmol·g^-1·h^-1, higher obviously than CO yields of other samples. Finally, the characterization analysis results show that the assistance of EDTA could not only regulate the structure morphology of BiYO₃, but also broaden the light response and enhance the separation efficiency of photogenerated electron-hole pairs, and consequently improve the photocatalytic CO₂ reduction performance. The research in this paper provides basic scientific data for the investigation on novel highly-effective B-Y-O photocatalytic system.

Key words: BiYO₃, EDTA-assisted hydrothermal method, photocatalysis, CO₂ reduction, action mechanism, carbon neutralization