Construction of visible light-responsive Z-scheme CdS/ BiOI photocatalyst with enhanced photocatalytic CO_2 reduction activity

摘要

Rational construction of Z-scheme photocatalysts and exploration of the Z-scheme charge transfer mechanism have drawn much attention in the field of CO2 reduction because of its great potential to alleviate energy crisis and environmental problems. In this study, a series of Z-scheme CdS/BiOl composites were constructed by depositing CdS nanoparticles on the surface of BiOl nanosheets. The synthesized materials were characterized comprehensively, and their photoreduction CO2 activities were evaluated. The results show that the composites exhibit higher photoreduction CO2 activity under visible light irradiation (lambda > 400 nm) than pure CdS and BiOl. The yields of CO and CH4 for the optimal composite after 3 h irradiation are 3.32 and 0.54 mu mol/g, respectively. The improved photocatalytic activity is attributed to Z-scheme transfer mode of the photogenerated charges in the composites. The mechanism of CO2 reduction is proposed and verified experimentally.