Solar exfoliated graphene and its application in supercapacitors and electrochemical H2O2 sensing

Abstract

In the present study, graphene nanosheets are synthesized using sunlight irradiation focussed onto graphite oxide. The morphological characteristics of graphene are examined using Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). Raman spectroscopy and X-ray diffraction (XRD) are used for the structural characterization of the sample. The electrochemical performance is evaluated using cyclic voltammetry (CV), charge-discharge characteristics and impedance spectroscopy. A high specific capacitance value of 223 F g-1 is obtained using cyclic voltammetry. The electrochemical detection of H<inf>2</inf>O<inf>2,</inf> a common biological species using solar graphene is demonstrated. The impedance spectroscopy and CV are used to study the electrocatalytic activity of the material. High sensitivity of 64.79 ?A mM-1 cm-2 is reported. © 2015 Elsevier Ltd. All rights reserved.