Synthesis of graphene via ultra-sonic exfoliation of graphite oxide and its electrochemical characterization

• Published in: Materials chemistry and physics Vol. 206; pp. 7 - 11
• Main Authors: Asgar, Hassnain, Deen, K.M., Riaz, Usman, Rahman, Zia Ur, Shah, Umair Hussain, Haider, Waseem
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 15.02.2018; Elsevier BV
• Subjects: Adsorption; Behavior; Diffraction; Diffraction patterns; Electrochemical analysis; Electrochemical impedance spectroscopy; Functional groups; Graphene; Graphite; Studies; Synthesis; X ray photoelectron spectroscopy
• ISSN: 0254-0584; 1879-3312
• DOI: 10.1016/j.matchemphys.2017.11.062

A direct method of producing graphene from graphite oxide (GO) via ultra-sonication is presented in this work. The synthesis of graphene was validated through IR, XRD, Raman, and XPS analyses. Moreover, the diffraction pattern obtained from TEM also validated the formation of graphene with characteristics (002) plane. The electrochemical behavior of GO and graphene was evaluated by electrochemical impedance spectroscopy and linear sweep voltammetry in 0.5M KOH solution. The relatively larger effective pseudocapacitance and broad current peak exhibited by GO in the LSV plots was related with the dominant adsorption of ‘Hads’ during reduction of water. It has been considered that large overpotential and relatively higher current response exhibited by GO compared to graphene was associated with the preferential adsorption of Hads in the presence of surface functional groups. •A relatively direct synthesis method for production of graphene is presented.•IR, Raman and XRD analyses confirmed formation of graphene starting from graphite.•XPS and TEM characterization validated the formation of graphene.•Electrochemical response of GO and graphene was evaluated in de-aerated 0.5M KOH.•Presence of functional groups in GO resulted in improved values of Rct and Ceff,p.