Selected growth of second phase on BiOBr facets via spatial charge separation towards enhanced photocatalysis activity

Abstract The recombination rate of electrons and holes determine the photocatalytic effect. Au nanoparticle (NPs) were loaded on the (110) plane of BiOBr via a ultrasonic method while PbO 2 NPs were loaded on the (001) plane. The ultrasound not only promoted the formation of the NPs but also resulted indirectionally transfer of electrons and holes in the different crystal planes, where electronsmainly exist in (110) planes while holes accumulate on (001) planes. Namely, ultrasonic waves caused BiOBr layer spacing to increase and destroy the balance of its built-in electric field. The loading of Au NPs enhanced the photocatalytic performance.