High-performance supercapacitor b ased on Cl-doped reduced graphene oxide

Heteroatom doping has been proven as an effective way to tailor the properties of graphene and render its potential use for energy storage devices. In this work, we report a facile method to synthesis of reduced graphene oxide (RGO) from graphite electrodes using ionic liquid-assisted electrochemical exfoliation and the competent doping of RGO by Chlorine (Cl-RGO) in solution phase. Its capacitive performance was calculated by cyclic voltammetry and charge–discharge cycling in 6M KOH solution. The characterization of synthesized catalysts has been investigation by FT-IR, Raman, XRD and XPS techniques. We have evaluated the effectiveness of doping and performed by electrochemical measurements (involving cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy). It was found that the chlorine groups making the as-prepared Cl-RGO exhibited remarkably enhanced electrochemical performance when used as electrode materials in supercapacitors. The supercapacitor based on the Cl-RGO exhibited a high specific capacitance of 180.5 F g-1 at current density of 1 A g-1 and remains a relatively high capacitance even at a high current density more than RGO.