Z-scheme indium sulfide/bismuth oxybromide heterojunctions with enhanced visible-light photodegradation of organics

A series of Z-scheme In2S3/BiOBr heterojunctions were synthesized through a two-step hydrothermal method. The results showed that the optoelectronic dynamics of carrier separation efficiency, charge transport and electron/hole recombination rate were improved greatly. As a result, the photocatalytic activity of In2S3/BiOBr heterojunctions was greatly enhanced under visible-light irradiation. This work will provide a better insight into the formation mechanism BiOBr-based Z-scheme heterojunctions with high photocatalytic performance. [Display omitted] •Z-scheme In2S3/BiOBr heterojunctions were prepared by a two-step hydrothermal method.•The optoelectronic dynamics was tuned to an optimal domain through changing the contents of In2S3.•The photocatalytic activity of Z-scheme In2S3/BiOBr heterojunctions was greatly enhanced under visible-light irradiation.•Z-scheme In2S3/BiOBr heterojunctions demonstrated a high photocatalytic stability in 4 runs. Heterojunction photocatalysts with intimate contact are very promising for organics photodegradation due to their high efficiency in enhancing the light absorption, inhibiting the carrier recombination and improving the photogenerated electron/hole separation. In this study, we demonstrated a two-step hydrothermal method to construct indium sulfide/bismuth oxybromide (In2S3/BiOBr) heterojunctions for the first time. Importantly, the optoelectronic dynamics of carrier separation efficiency, charge transport and electron/hole recombination rate were tuned to an optimal domain through a series of experiments. As a result, the photocatalytic activity of In2S3/BiOBr heterojunctions was greatly enhanced under visible-light irradiation. The as-synthesized IS/BOB-0.2 heterojunctions exhibited the highest photocatalytic ability, which was approximately 4.75 times and 11.26 times higher than that of pure BiOBr and TiO2 P25 catalysts. This work will provide a better insight into the formation mechanism BiOBr-based Z-scheme heterojunctions with high photocatalytic performance.