Nanohybrids of silver nanoparticles grown in-situ on a graphene oxide silver ion salt: simple synthesis and their enhanced antibacterial activity

Abstract

Advanced antimicrobial agents that treat infectious diseases are greatly needed. Various silver-based nanomaterials have been developed and are considered potential candidates for many commercial products, but they lack durability and adequate antibacterial activity. A new class of nanohybrids of silver nanoparticles (AgNPs) grown in-situ on graphene oxide (GO) using a silver ion salt was synthesized by a simple ultrasonic mixing method. The structure and composition of the nanohybrids were investigated by SEM, TEM, FTIR, TGA, XRD and XPS. Results indicated that GO acts not only as a negatively charged macromolecule for capturing Ag+ ions, but also a reducing agent to reduce the Ag+ ions to AgNPs. The heterogeneous structure leads to abundant well-dispersed AgNPs and Ag+ ions on the GO support. The as-prepared nanohybrids make full use of the advantages of both AgNPs and GO-Ag+ salts, leading to improved and long-term antibacterial activity against both S.aureus and E. coli.