International Journal of Hydrogen Energy, Vol.43, No.3, 1667-1674, 2018
Supercapacitive properties of activated carbon electrode using ammonium based proton conducting electrolytes
In this study, we demonstrated the usefulness of proton conducting electrolytes (such as ammonium thiocyanate (NH4SCN) and ammonium nitrate (NH4NO3)) for electrochemical energy storage devices using activated carbon (AC) as the electrode material. The cyclic voltammetry analysis revealed the presence of rectangular shaped cyclic voltammograms indicating the presence of electrical double layer capacitance in AC electrode using NH4SCN and NH4NO3 electrolytes. The mechanism of charge-storage in AC electrode using the proton conducting electrolytes has been studied in detail using electrochemical impedance spectroscopy (Nyquist and Bode plots). The galvanostatic charge-discharge analysis revealed that a maximum specific capacitance of AC electrode using NH4SCN and NH4NO3 electrolytes was found to be 136.75 mF cm(-2) and 113.38 mF cm(-2) at a current density of 0.5 mA cm(-2). This study would open a new avenue for the use of ammonium based proton conducting electrolytes for supercapacitor applications. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.
Keywords:Proton conducting electrolytes;Activated carbon;Cyclic voltammetry;Nyquist plot;Bode phase angle plot