Unlocking the potential of magnetic bio-char as a low-cost cathode material for the supercapacitor application

Abstract

Modification of biochar is an intriguing idea to enhance the electrochemical performance of biochar-based electrode materials for supercapacitors. Herein, magnetic biochar (MBC) was successfully prepared via low-cost pyrolysis techniques. The as-synthesized MBC has a carbon-rich structure and a higher surface area of 14.14 m2 g−1 which makes it suitable for use as an electrode. The as-fabricated optimized composite (MBC) exhibits amazing super capacitive performance in terms of high specific capacitance (1397 F/g), good cycle stability, and magnificent rate capability when first served as electrodes. Moreover, the symmetric supercapacitor device was synthesized by using MBC as a cathode and anode. Because of their porous structure, complementary potential windows (0–1.3 V) of two electrodes, rate capabilities, and high specific capacitance, the device exhibits desirable electrochemical properties. At 900 W/kg of power density, the symmetric supercapacitor has an energy density of 12.2 Wh/kg. Based on these optimistic results, we need to do further research to create high-energy and power-density devices for practical applications.