Z-scheme transfer pathway assisted photoelectrocatalyst Zn2SnO4/rGO/Ag/AgBr for organic pollutants treatment

Rational design of photoelectrode with high visible light utilization rate and separation efficiency of electron-hole pairs is the key step in photoelectrocatalytic technology. In this work, Z-Scheme photoelectrocatalyst (ZTO/rGO/Ag/AgBr) was synthesized by hydrothermal and photo-reduction process. Comparing with pure Zn 2 SnO 4 (ZTO), adding reduced graphene oxide (rGO) effectively improved electrons transfer efficiency. Notably, the addition of Ag/AgBr not only broaden the visible light response range of ZTO, but also accelerated the separation of photo-generated electron-hole pairs, and constructed all-solid-state Z-Scheme heterojunction . Meanwhile, DFT calculation showed that Ag metal on rGO surface could act as active site for organic dyes degradation . Moreover, the addition of extra bias potential during photoelectrochemical process not only accelerate the migration of carriers, but also inhibit the recombination of photo-generated electron-hole pairs. Methylene blue (MB) could be effectively removed during photoelectrochemical reaction process, which was attributed to hydroxyl radical (•OH) and superoxide radical (•O 2 - ). In this work, Z-Scheme transfer pathway, assisted photoelectrocatalytic technology, is a feasible strategy for improving catalytic performance.