Functionalized silver nanoparticles with graphene quantum dots shell layer for effective antibacterial action

Graphene quantum dots (GQDs) as a shell layer was coated on the surface of silver nanoparticles (AgNPs) to obtain an effective antibacterial composite (GQDs@AgNPs). The structures and antibacterial properties of AgNPs, GQDs, and GQDs@AgNPs were studied. SEM and TEM results indicated that GQDs were coated on the surface of AgNPs. For GQDs@AgNPs, the core size of AgNPs was about 20 nm, and the shell thickness of GQDs was about 5 nm. The formation and antibacterial mechanism of GQDs@AgNPs composite materials were discussed in detail. It showed excellent antibacterial properties for E. coli and S. aureus.