Charge transfer channels of silver @ cuprous oxide heterostructure core-shell nanoparticles strengthen high photocatalytic antibacterial activity.

Marine biological fouling has always been a hot research topic. In this study, silver @ cuprous oxide (Ag@CuO) core-shell nanoparticles were synthesized via in-situ synthesis method and developed an outstanding antibacterial activity. The bacteriostasis efficiency of Ag@CuO reached to 99% and 98% against Staphylococcus aureus and Pseudomonas aeruginosa, respectively. The minimum inhibitory concentration of Ag@CuO decreased from 113.6 μg/mL to 56.8 μg/mL compared with CuO. Ag@CuO had better antibacterial activity than CuO with lower content of CuO and was more environment friendly. The heterostructure formed at the interface between Ag and CuO promoted the separation and diffusion of photogenerated electron-hole pairs through the charge transfer channel and promoted the generation of reactive oxygen species. The outstanding antibacterial activity of Ag@CuO was strongly depended on the generation of the reactive oxygen species. Density functional theory and finite element method calculations demonstrated that the structure of core-shell improved photocatalytic efficiency. Additionally, synergetic effect of released Ag and Cu also enhanced the bacteriostasis rate and the long-term antifouling performance in 60 days. Hence, the synthesized core-shell Ag@CuO can be applied as novel antifoulants in the marine field.