Photoinduced Ce-MoS2/WO3 nanocomposites with enhanced photodynamic and enzyme-like activity for rapid sterilization

Bacterial infections is a serious threat to our health. Thus, there is an urgent need to develop a new effective antibacterial agent. In this work, we developed a novel and environmentally friendly Ce-MoS2/WO3 nanocomposite antimicrobial agent with excellent antimicrobial effect and the antimicrobial efficiency against E. coli reached to 97.8% under visible light irradiation. Electron paramagnetic resonance (EPR) spectra showed that the large amounts of superoxide anion radical (O-center dot(2)-) and hydroxyl radical ((OH)-O-center dot) were generated by the nano-composites under light excitation, which were the main active substances causing oxidative damage for bacteria. Simultaneously, the photothermal curve and peroxidase activity test of Ce-MoS2/WO3 nanocomposites confirmed it has the excellent photothermal effect and enhanced enzyme-like activity, which further assisted in antibacterial effects. Ce doping enlarges the layer spacing of MoS2 and forms lattice dislocations and distortions, effectively increasing the defect sites at the layer edges, and the coupling of Ce-MoS2 and WO3 to construct heterojunctions reduces the charge separation rate, which further improves the photocatalytic antibacterial performance and enzyme-like antibacterial activity of Ce-MoS2/WO3 nanocomposites.