Ag2S@WS2 Heterostructure for Rapid Bacteria-Killing Using Near-Infrared Light

On a global scale, bacterial infection has become a huge threat to human health. Taking into consideration the increasing drug-resistance bacteria, it is urgent to develop novel nonantibiotics strategies to kill bacteria rapidly. Herein, Ag 2 S@WS 2 was developed as a new kind of antibacterial agent, where exfoliated WS 2 nanosheets were decorated with Ag 2 S nanoparticles through in situ growth. Under near-infrared (NIR) light irradiation (808 nm), the tight contact between Ag 2 S and WS 2 endowed the composite with outstanding photocatalytic property, which was attributed to effective separation of photoactivated electronics and holes. Because of the synergistic effect of photocatalytic and photothermal properties, highly effective antibacterial efficacy could be achieved for Ag 2 S@WS 2 within 20 min NIR light irradiation, that is, 99.93% toward Staphylococcus aureus and 99.84% toward Escherichia coli . Moreover, the in vitro cell culture test showed that the synthesized Ag 2 S@WS 2 was noncytotoxic. These results demonstrate that Ag 2 S@WS 2 can be a promising material for rapid and highly effective disinfection under NIR irradiation.