Novel BiOI/BiOBr heterojunction photocatalysts with enhanced visible light photocatalytic properties

摘要

A novel heterojunction photocatalyst BiOI/BiOBr was synthesized by a simple modified deposition-precipitation method. Several characterization tools including XRD, SEM, HRTEM and UV-vis DRS were employed to study the phase structures, morphologies and optical properties of the samples. BiOI/BiOBr exhibited higher photocatalytic activity than single BiOI and BiOBr for the degradation of methyl orange (MO) under visible light (λ>420 nm). This result can be due to the formation of the heterojunction between BiOI and BiOBr, which can separate photogenerated carriers efficiently. The photocatalytic mechanism study demonstrates that ~·O_2~- and h~+ are the main reactive species while ~·OH can be negligible.