title: Covalent surface modification of chemically derived graphene and its application as supercapacitor electrode material.
abstract: A simple and effective method using 6-amino-4-hydroxy-2-naphthalenesulfonic acid (ANS) for the synthesis of water dispersible graphene has been described. Ultraviolet-visible (UV-vis) spectroscopy reveals that ANS-modified reduced graphene oxide (ANS-rGO) obeys Beers law at moderate concentrations. Fourier transform infrared and X-ray photoelectron spectroscopies provide quantitative information regarding the removal of oxygen functional groups from graphene oxide (GO) and the appearance of new functionalities in ANS-rGO. The electrochemical performances of ANS-rGO have been determined by cyclic voltammetry, charge-discharge and electrochemical impedance spectroscopy analysis. Charge-discharge experiments show that ANS-rGO is an outstanding supercapacitor electrode material due to its high specific capacitance (375 F g(-1) at a current density of 1.3 A g(-1)) and very good electrochemical cyclic stability (∼97.5% retention in specific capacitance after 1000 charge-discharge cycles). ANS-rGO exhibits promising characteristics with a very high power density (1328 W kg(-1)) and energy density (213 W h kg(-1)).
authors.affiliation: Surface Engineering & Tribology Division, Council of Scientific and Industrial Research-Central Mechanical Engineering Research Institute, Durgapur - 713209, India. tkuila@gmail.com.
authors.forename: Milan
authors.initials: M
authors.lastname: Jana
authors.forename: Partha
authors.initials: P
authors.lastname: Khanra
authors.forename: Naresh Chandra
authors.initials: NC
authors.lastname: Murmu
authors.forename: Pranab
authors.initials: P
authors.lastname: Samanta
authors.forename: Joong Hee
authors.initials: JH
authors.lastname: Lee
authors.forename: Tapas
authors.initials: T
authors.lastname: Kuila