Mesoporous Activated Carbon Derived from Corn Stalk as Supercapacitor Electrodes

Activated carbon (AC) is a promising electrode material for supercapacitors due to its excellent cycling stability. However, the synthesis of AC with significant performance is still limited. The development of AC preparation is important for supercapacitors. Herein, AC derived from corn stalks was prepared. The crystal structure and morphological properties can be modified by changing the ratio of corn stalk and potassium hydroxide (CS: KOH). Specific capacitances were 63.53, 88.24, and 70.5 F g-l in 1 M KOH electrolyte at the current density of 1 A g-l for the CS: KOH ratios of 1:1, 1:2, and 1:3, respectively. Moreover, it still maintained a capacitance retention ratio of 92.4 % at a current density of 8 A g-l after 50,000 cycles. Hence, based on the insights gained, optimized synthesis routes of AC can provide a reference for high-performance and long-life-span supercapacitor electrodes.