Abstract:
Stable ionic liquids (ILs) are promising materials for extending the potential applications of electrolytes. Herein, the effects and capacitance performance of various ILs consisting of the same 1-butyl-3-methylimidazolium ([bmim]) cation and three different anions: bromide (Br-), chloride( Cl-), and hexafluorophosphate (PF6-) have been investigated with activated carbon (AC) derived from banana leaves for supercapacitor (SCs) applications. The specific capacitance (Csp) values were obtained 177, 318, and 280 F g-1 in [bmim]Br, [bmim]Cl, [bmim]PF6 electrolytes, respectively. The effect of the size of anions and polarizability has been found to affect the capacitance performance. In [bmim]Cl, the AC has obtained the best capacitance performance and rate capability. A comparison of electrochemical performance revealed that the electrolyte anions have a significant effect on the SCs efficiency. A mini-prototype device has been prepared to demonstrate the practicality of the AC and [bmim]Cl electrolytes. This study is expected to broaden the applications of ILs for SC devices.
