BiOBr photocatalysts with tunable exposing proportion of {001} facets: Combustion synthesis, characterization, and high visible-light photocatalytic properties

BiOBr photocatalysts were synthesized by the combustion method. The BiOBr nanosheets possessing pure tetragonal BiOBr phase with high ratio of {001} facets exposure were obtained. The thickness of BiOBr nanosheets, in other words, the exposing proportion of {001} facets can be modulated through changing the added amount of ammonium bromide. The band gap energy of BiOBr was increased with larger exposing proportion of {001} facets. BiOBr with the thinest sheets exhibited the best photocatalytic activity of Rhodamine B under visible-light irradiation. To the end, the corresponding plausible growth mechanism of BiOBr was presented.