Solid-phase synthesis of Bi3-xYxO4Cl solid solution for visible-light photocatalytic hydrogen generation

The solid solution constructed by two or more semiconductors with different bandgaps can effectively modulate the energy band, satisfying the redox potential for both H+/H-2 and O-2/H2O. In this paper, Sillen-Aurivillius compounds with layered structure Bi3O4Cl and Y3O4Cl solid solution (Bi3-xYxO4Cl) were successfully synthesized by the solid-phase method. The absorption edge of Bi3-xYxO4Cl could be dramatically changed from about 500-740 nm with the increase of Bi elements, which accounted for the entire UV-Vis region of the solar spectrum. Furthermore, the bandgaps for Bi3-xYxO4Cl could be adjusted from about 2.6-2.0 eV with the decreased Y/Bi ratio from 2 to 0.2. Significantly, the conduction band minimum energy (CBM) of Bi3-xYxO4Cl all satisfied the redox potential for H+/H-2, which showed excellent visible-light photocatalytic water splitting. (C) 2021 Elsevier B.V. All rights reserved.