A photo catalyst of cuprous oxide anchored MXene nanosheet for dramatic enhancement of synergistic antibacterial ability

Ti3C2Tx (MXene) as a two-dimensional material has attracted numerous attentions in photocatalysis and antibacterial, and the effectiveness of MXene for photocatalysis triggered antibacterial is in urgent need of development. Herein, we synthesized a novel cuprous oxide (Cu2O) anchored MXene nanosheet. Cu2O nanospheres can be uniformly anchored on the surface of MXene firmly due to the electrostatic effect between single-layer MXene and Cu2O nanospheres. In comparison with MXene, Cu2O and mixture (MXene and Cu2O), Cu2O/MXene nanosheet exhibits an excellent antibacterial activity against S. aureus and P. aeruginosa, whose bacteriostasis efficiencies sharply increased to 97.04% and 95.59%, respectively. Photoluminescence spectroscopy reveals that the incorporation of MXene and Cu2O can effectively prevent the recombination of electron-hole pairs of Cu2O and present a high photocatalytic disinfection. Single-layer MXene with large surface area accepts electrons from Cu2O, leading to abundant electrons on the surface of MXene, which provide better charge transfer between bacteria and Cu2O/MXene nanosheets. In addition, density functional theory calculations were used to investigate an optimized band structure of Cu2O-MXene as well as its strong electronic interactions, which are essential for photocatalysis and ROS generation. Finite element method further revealed that MXene promoted an enhancement of surface plasmon resonance to generate ROS on the surface of Cu2O/MXene. Furthermore, Cu2O/MXene shows a synergistic antibacterial effect of MXene accelerating photoelectron transportation, Cu2O antimicrobial and photocatalysis, elevated ROS production ability, and surface plasmon resonance action on the surface of Cu2O/MXene.