A PPy/MoS2 core–shell heterojunction modified by carbon dots exhibits high photocatalytic antibacterial performance

Abstract

Developing effective antimicrobials while avoiding drug resistance remains a challenge. Using a simple in situ polymerization method, this study incorporated carbon quantum dots (CQDs) in a three-component composite PPy/MoS₂/CQD with a core–shell structure. The as-prepared composites indicated photocatalytic antibacterial activity. In the vitro antibacterial trials, a much higher bactericidal rate was achieved upon irradiation with visible light for 24 hours than under dark conditions. Moreover, the antibacterial effects of PPy/MoS₂/CQD composites indicated similar antimicrobial effects against both general and drug-resistant bacteria owing to their unique antimicrobial mechanism, wherein the core–shell structure enhances the lifetime of photo-induced electrons and holes, leading to the effective production of a large number of reactive oxygen species and inhibiting bacteria growth. In conclusion, PPy/MoS₂/CQD nanomaterials are promising antimicrobials for treating both regular and drug-resistant bacteria.