Reactive Red 198 as high-performance redox electrolyte additive for defective mesoporous carbon-based supercapacitor

In the present study, defective mesoporous carbon (DMC) was successfully synthesized via a facile hard templating route. Thanks to its interconnected porous framework with a high specific surface area of 1350 m2 g-1 was adapted as electrode material for supercapacitor application. In addition, the possibility of Reactive Red 198 as novel and efficient redox mediator was investigated using different techniques. The supercapacitor performance of DMC electrode was significantly enhanced through introducing of 5 mM Reactive red 198 into 1 M aqueous solution of H2SO4. Analysis of scan rate by Trasatti method indicated that 86.5% of the overall capacitance was originated through the insertion of Reactive Red 198. The presented supercapacitor system exhibited a high specific capacitance of 282 F g-1, a good rate capability of 158 F g-1 at 10 A g-1 with 56% capacitance retention. Moreover, reasonable cycle durability with about 73% retention after a prolonged successive cycling process (2000 cycles) at current densities of 2 A g-1 was obtained. Finally, the specific en-ergy of 9.8 W h kg-1 at specific power of 254 W kg-1 was achieved for symmetric device which shows 2.3 times increase in specific Energy over the DMC electrode with pure H2SO4 electrolyte. (c) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.