Eigenstate polyaniline deposited on carbon cloth with optimized electrochemical performance for supercapacitors

Abstract

Abstract In this paper, conductive carbon cloth (CC) is applied as substrate, polyaniline (PANI) was synthesized on the surface of CC (CC/PANI) by cyclic voltammetric polymerization, and then fully soaked in ammonia to obtain eigenstate polyaniline (EB) hybrid electrode material (CC/EB), Meanwhile, the electrochemical properties of CC/EB in acidic electrolyte and acidic electrolyte containing Mn2+ were investigated by cyclic voltammetry (CV), galvanostatic charge–discharge (GCD) test and electrochemical impedance spectroscopy (EIS) in three-electrode system. The results indicated that compared with protonic acid electrochemically doped EB, Mn2+ doping can effectively improve the pseudo-capacitance of EB. in acid electrolyte (1 M H2SO4) containing 0.3 M MnSO4, the specific capacitance of CC/EB reaches 942.9 mF/cm2 at a current density of 1 mA/cm2, significantly higher than CC/EB (638.3 mF/cm2) and CC/PANI (440.0 mF/cm2) in 1 M H2SO4. CC/EB also exhibits good cycling stability in H2SO4 electrolyte containing 0.3 M MnSO4, retaining 73.6% at a current density of 5mA/cm2 of the initial capacitance after 3000 cycles. Furthermore, a flexible asymmetric supercapacitor (ASCs) based on EB/CC and active carbon (AC) with the optimized gel electrolyte（PVA-H2SO4（0.3 M Mn2+）is assembled, and the system delivers an energy density of 2.57 mWh/cm3 at a power density of 18.3 mW/cm3 at 1 mA/cm2, showing good application potential.