Solvothermal synthesis of BiOBr<inf>x</inf>I<inf>1-x</inf> (x = 0.0–1.0) solid solutions used for adsorption and photodegradation of cationic and anionic dyes

Abstract

BiOBrxI1-x (x = 0.0, 0.25, 0.50, 0.75 and 1.0) solid solutions were prepared by a simple solvothermal method. X-ray diffraction patterns were indexed to the combination of tetragonal BiOBr and BiOI phases. Their morphologies were gradually changed from pure BiOBr nanoplates to BiOBrxI1-x (x = 0.25, 0.50 and 0.75) regular architecture flowers and to pure BiOI hollow microspheres. The photocatalyst was possessed negative surface charge which has the benefit of good adsorption and photodegradation of cationic rhodamine B (RhB) and methylene blue (MB) dyes. Thus, the photodegradation of RhB and MB over BiOBr0.25I0.75 microsphere flowers under visible light irradiation was higher than that of anionic methyl orange (MO) dye. In this research, ●O2– radical was the key active species used for the photocatalytic process.