A facile synthesis of PEGylated CuO@SiO/MnO nanocomposite as efficient photo-Fenton-like catalysts for methylene blue treatment.

The removal of toxic organic dyes from wastewater has received much attention from the perspective of environmental protection. Metal oxides see wide use in pollutant degradation due to their chemical stability, low cost, and broader light absorption spectrum. In this work, a CuO-centered nanocomposite CuO@SiO/MnO-PEG with an average diameter of 52 nm was prepared for the first time a wet chemical route. In addition, highly dispersed MnO particles and PEG modification were realized simultaneously in one step, meanwhile, CuO was successfully protected under a dense SiO shell against oxidation. The obtained CuO@SiO/MnO-PEG showed excellent and stable photo-Fenton-like catalytic activity, attributed to integration of visible light-responsive CuO and HO-responsive MnO. A degradation rate of 92.5% and a rate constant of 0.086 min were obtained for methylene blue (MB) degradation in the presence of HO under visible light for 30 min. Additionally, large amounts of •OH and O species played active roles in MB degradation. Considering the enhanced degradation of MB, this stable composite provides an efficient catalytic system for the selective removal of organic contaminants in wastewater.