Visible-light-driven enhanced antibacterial and biofilm elimination activity of graphitic carbon nitride by embedded Ag nanoparticles

Semiconductor nanomaterials with photocatalytic activity have potential for many applications. An effective way of promoting photocatalytic activity is depositing noble metal nanoparticles (NPs) on a semiconductor, since the noble metal NPs act as excellent electron acceptors which inhibit the quick recombination of the photoexcited electron-hole pairs and thereby enhance the generation of reactive oxygen species (ROS). Herein, a highly effective platform, graphitic carbon nitride (g-C₃N₄) nanosheets with embedded Ag nanoparticles (Ag/g-C₃N₄), was synthesized by a facile route. Under visible light irradiation, the ROS production of Ag/g-C₃N₄ nanohybrids was greatly improved compared with pristine g-C₃N₄ nanosheets, and moreover, the nanohybrids showed enhanced antibacterial efficacy and ability to disperse bacterial biofilms. We demonstrate for the first time that the Ag/g-C₃N₄ nanohybrids are efficient bactericidal agents under visible light irradiation, and can also provide a new way for biofilm elimination. The enhanced antibacterial properties and biofilm-disrupting ability of Ag/g-C₃N₄ nanohybrids may offer many biomedical applications.