Abstract
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 cm2 and 113.38 mF cm2 at a current
density of 0.5 mA cm2. This study would open a new avenue for the use of ammonium
based proton conducting electrolytes for supercapacitor applications.