Facile and green synthesis of graphene

Abstract

Herein, we report a simple, facile, green and cost effective strategy for the synthesis of graphene using naturally available anti-oxidants such as carotenoids present in vegetable (carrot, sweet potato, etc.) extracts. In this work, we have employed carrot extract to reduce graphene oxide to reduced graphene oxide. A red shift (in the λ_max from 230 nm to 270 nm) during the course of the reduction of GO clearly indicates the effective restoration of the sp² graphitic carbons. In addition, we have also noticed the colour change of the reaction mixture from yellowish brown to black after 1 hour, thereby indicating the reduction of GO to reduced graphene oxide (Ct-RGO). Further, an increase in the D/G ratio value of GO from 0.979 to 1.198 after the complete reduction indicated the effective restoration of the in plane sp² domains in the Ct-RGO. The morphology and conductivities of the Ct-RGO are characterized by several characterization techniques such as UV, FT-IR, Raman, XRD, XPS, SEM, TEM, AFM and EIS. The green synthesis reported in this work is expected to yield a biocompatible graphene material suitable for futuristic biological applications.