MCr–LDHs/BiOBr heterojunction nanocomposites for efficient photocatalytic removal of organic pollutants under visible-light irradiation

Abstract

The removal of low concentration pollutants in water is very important for environmental remediation. Herein, MCr–LDHs/BiOBr (M = Zn, Ni, Cu) heterojunction nanocomposites were fabricated by a facile rapid crystallization method. Visible-light responsive heterojunctions could be formed efficiently at the intimately contacted interface between BiOBr nano-crystallites and LDHs nano-flakes, which showed higher photocatalytic degradation activities of cationic, anionic, and electrically neutral organic pollutants than pristine LDHs and BiOBr. Degradation of 99.5% Rhodamine B, 80% methyl orange, and 97% bisphenol A could be achieved by the composite catalysts under visible-light irradiation in 15 min, 60 min, and 40 min, respectively, and cycling test proved the good reusability of composite catalysts as well. Benefitting from superior adsorption properties for ionic organic pollutants, and effective separation and transition of photogenerated holes and electrons, the MCr–LDH/BiOBr composite catalysts exhibit wide applicability for removal of various organic pollutants in water and have potential application prospects in the future.