Singlet oxygen generation boosted by Ag-Pt nanoalloy combined with disordered surface layer over TiO2 nanosheet for improving the photocatalytic activity

The activation of molecular oxygen with photoinduced charge carriers are highly vital in photocatalysis. Here, the synergetic effects of disordered surface layer and Ag-Pt nanoalloy over TiO2 nanosheet on the improved photocatalytic activity was proposed. The nanocomposites exhibited enhanced photocatalytic performance in selective oxidation of benzylamine to imine under UV-visible irradiation. More importantly, the synergetic effect of nanoalloy and surface oxygen vacancy boosted the generation of singlet oxygen in the selective oxidation of benzylamine. The regulation of thickness of disordered surface layer and composition of Ag-Pt nanoalloy over nanosheet TiO2 promoted the separation efficiency and mobility of charge carriers, resulted from the changed electronic structure of surface layer and nanoalloy. These findings provide an avenue for the design of nano-composite photocatalysts combined defect engineering and nanoalloy modification to improve the photocatalytic activity.