▎ 摘　　要

Graphene based materials have attracted huge interest in recent years due to their outstanding properties and applications in various fields including bioengineering, electronics, nanotechnology, composite materials and many more. Despite numerous reports on synthesis of graphene, the mass production of high quality graphene in an inexpensive and eco-friendly method has remained as a challenge. In this work, we present a simple and green method for biosynthesis of graphene by using nontoxic reducing agent from Allium Cepa (onion) extracts. Modified Hummers' method was used to synthesis the Graphene oxide (GO) and extracts from Allium Cepa was used as reducing agent. The prepared graphene was analyzed by Raman spectroscopy, XRD, FTIR, SEM, TEM and XPS. The experimental results showed that GO was successfully reduced to graphene using onion extract. The Raman spectroscopy results, XPS results and XRD results confirmed the reduction of GO to graphene. The SEM and TEM results also reconfirmed the reduction of GO into graphene, where GO exhibited different morphologies, i.e. hexagonal larger sheets than graphene. The antibacterial properties of the graphene were studied against two gram-negative and gram-positive bacteria. Graphene inhibited cell growth, which proves that our prepared graphene can be useful as an antimicrobial agent against different microorganisms. This work thus reports the design of a novel, facile synthetic route for a new production method of graphene. (C) 2018 Published by Elsevier B.V.