Constructing 2D/1D heterostructural BiOBr/CdS composites to promote CO2 photoreduction

Abstract

Herein, a generalizable strategy using the solvothermal process to obtain the heterostructural composites between BiOBr nanosheet and CdS nanorods is presented. Using a facile hydrothermal method, the CdS nanorods were anchored onto BiOBr nanosheets with average scales ranging from 10 to 500 nm to build up the heterostructure. The improvement of the efficiency of charge separation through the construction of 2D/1D heterojunction was confirmed by SEM, TEM, XPS, photocurrent, and AC impedance. CO2 photoreduction was employed to study the photocatalytic activities of the as prepared composites. The heterostructural BiOBr/CdS composites owned better activity than both the pure BiOBr nanosheets and pure CdS nanorods. Most significantly, the yield of CO during photocatalytic reduction reaction with BiOBr/CdS-5% catalyst was measured to be 13.6 μmol g−1, which was 1.8 times larger than that with BiOBr nanosheets and 6.4 times larger than that with CdS nanorods during 3 h simulative sunlight exposure. The optimized photocatalytic property of heterostructural BiOBr/CdS-5% composite could be attributed to the wide sunlight response range, large specific surface area, and effective separation of photoelectrons-holes from the heterostructure between BiOBr nanosheets and CdS nanorods.