Highly Enhanced Photoelectrocatalytic Oxidation via Cooperative Effect of Neighboring Two Different Metal Oxides for Water Purification

The generation of hydroxyl radicals derived from water molecules plays a pivotal role in attacking organic pollutants for the photoelectrocatalytic (PEC) process. To promote the generation efficiency of hydroxyl radicals, remarkably efficient transportation of the induced carriers and water molecules is desirable. Here, we implemented a remarkably enhanced photoelectrocatalytic oxidation via cooperative effect of neighboring two different metal oxides, Bi2MoO6 and Sb-doped SnO2 nanosheets, for water remediation. To realize the highly efficient transportation of the induced carriers, the hierarchical architecture Bi2MoO6 wrapped Sb-doped SnO2 nanosheets are rationally designed and synthesized. Density functional theory (DFT) calculations demonstrate that water molecules prefer to be adsorbed on the surface of Sb-doped SnO2 nanosheets, producing hydroxyl radicals (center dot OH) on the surface of Bi2MoO6. The cooperation action between Bi2MoO6 and Sb-doped SnO2 nanosheets for the generation of hydroxyl radicals by water photoelectrolysis is enforced as follows: the Sb-doped SnO2 nanosheet layer can act as the supply station of water and rapidly transfer the water molecules to neighboring Bi2MoO6 to generate hydroxyl radical. This work may enlighten the design and construction of advanced photoanode materials for future scale-up of cost-effective water purification and environmental remediation.