Optimization of redox-active anthraquinone as electrode and electrolyte materials in supercapacitors.

This study demonstrates and characterizes a high energy density supercapacitor with anthraquinone (AQ) as the redox active material for the electrode and electrolyte. Optimal mass ratios of AQ are verified at both the electrode and in the electrolyte. Excellent electrochemical performance is achieved at an AQ mass ratio of 15 wt% in the activated carbon electrode and 0.02 wt% in the electrolyte, which is 1 M tetraethyl ammonium tetrafluoroborate in acetonitrile. The optimized supercapacitor containing an AQ electrode and AQ electrolyte provides an energy density of 178.9 Wh kg⁻¹ at a power density of 1600 W kg⁻¹, which retains 97% of its specific capacitance after 10,000 cycles.