Plasmonic molybdenum oxide nanosheets supported silver nanocubes for enhanced near-infrared antibacterial activity: Synergism of photothermal effect, silver release and photocatalytic reactions

[Display omitted] •MoO3-x-Ag hybrid nanostructures are designed as NIR light driven antibacterial agent.•MoO3-x-Ag exhibits excellent photothermal conversion abilities in killing bacteria.•Heat transferring from MoO3-x to Ag triggers the release of more Ag+ to kill bacteria.•Separated hot electrons and holes produce reactive species for the bacteria oxidation.•MoO3-x-Ag exhibits enhanced NIR antibacterial activity compared with MoO3−x and Ag. Plasmonic MoO3−x nanosheets supported Ag nanocubes were designed as high-efficient Near-infrared (NIR) light driven antibacterial agent. The as-designed MoO3−x-Ag not only significantly reduces the cost and toxicity of Ag, but also greatly enhances the antibacterial activity towards E. coli and S. aureus in comparison with bare MoO3−x and Ag upon NIR laser irradiation. Three effects are believed to contribute to this enhancement: (1) the plasmonic MoO3−x-Ag exhibits excellent NIR light absorption and photothermal conversion abilities, which help to kill bacteria; (2) NIR light induced heat in MoO3−x also diffuses to Ag nanocubes and triggers the release of more Ag+, leading to bacterial cell death; (3) under NIR light irradiation, hot electrons and holes are generated and separated through MoO3−x-Ag interface, which produces reactive species for the oxidation of out membrane of bacteria. The synergism of NIR light driven photothermal effect, silver release and photocatalytic reaction makes the designed plasmonic MoO3−x-Ag a promising antibacterial agent for cleaning the microbial contaminated water environment.