Novel I−-doped BiOBr composites: Modulated valence bands and largely enhanced visible light phtotocatalytic activities

Abstract

Novel I−-doped BiOBr (I-BiOBr) composites were prepared by a simple chemical precipitation method. The doped I− induced the light absorption of I-BiOBr broadening to visible light region remarkably. Under visible light (λ>400nm), I-BiOBr composites displayed much higher photocatalytic activities than pure BiOBr for degrading methyl orange. The newly formed I− impurity levels located on top of the valence band of BiOBr, determined by Mott–Schottky method, facilitated in generating more electron–hole pairs and further highly improved the photocatalytic activities of I-BiOBr samples.