Green synthesis of an Ag nanoparticle-decorated graphene nanoplatelet nanocomposite by using Cleistocalyx operculatus leaf extract for antibacterial applications

In the past few years, green synthesis has been extensively utilized as an environmentally friendly and affordable approach for the preparation of nanomaterials. Many extracts from plants have been employed as green reductants for these syntheses. For the first time, the Cleistocalyx operculatus leaf extract was employed as a green reductant to synthesize Ag nanoparticles decorated on the surfaces of graphene nanoplatelets. Moreover, the behavior of the components in the extract on the formation of the Ag nanoparticles is discussed herein. The prepared Ag nanoparticle/graphene nanoplatelet nanocomposite was characterized using X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy and mapping, and Fourier-transform infrared spectroscopy. The results show that the Ag nanoparticles were 20–40 nm in diameter and were uniformly distributed on the surface of the graphene nanoplatelets. In addition, the green-synthesized Ag nanoparticle/graphene nanoplatelet nanocomposite also demonstrated excellent antibacterial activity toward Escherichia coli, thereby showing its promise for use as a disinfectant. [Display omitted] •Simple extraction of Cleistocalyx operculatus leaves as a green reducing agent for nanomaterial synthesis.•The synthesis of nanocomposite using C. operculatus leaves extract is green and straightforward.•The Ag nanoparticles are uniformly distributed on the surfaces of the graphene nanoplatelets.•The green-synthesized nanocomposite exhibits excellent antimicrobial activity against E. coli and other bacterial strains.