Optimized mesopores enable enhanced capacitance of electrochemical capacitors using ultrahigh surface area carbon derived from waste feathers

Porous carbons with high specific surface area are critical engineering materials for current electrochem-ical capacitors (ECs) technology. Controlling the pore size distribution of porous carbons remains a sig-nificant challenge as it is a key aspect in many applications. Herein, we synthesized porous carbon as the electrode material of ECs by means of a two-step synthesis procedure using abandoned feathers as carbon precursor and potassium hydroxide as activating agent. The optimal sample (AFHPC-800-1:3) exhibited an ultra-high specific surface area (SBET) of 3474 m2/g and a huge total pore volume (VT) of 1.82 m3 g-1 as well as abundant small mesopores ranging from 2 to 5 nm in size. The ECs based on the AFHPC-800-1:3 electrode exhibited an ultra-high specific capacitance (Csp) of up to 709F g-1 at 0.5 A g-1. More interestingly, a capacitance of 212F g-1 was retained even at 100 A g-1, demonstrating excel-lent high-rate capacitive performance. Furthermore, the symmetrical capacitor yielded an excellent energy density of 35.1 Wh kg-1 when the specific power density was 625 W kg-1, substantiating the potential of the small mesopores in promoting the overall capacitance and energy density of electrode materials.(c) 2022 Elsevier Inc. All rights reserved.

Automated summary

Porous carbons with high specific surface area are crucial for electrochemical capacitors. In this study, porous carbon was synthesized using abandoned feathers and potassium hydroxide. The optimal sample exhibited ultra-high specific surface area and large pore volume. The resulting electrochemical capacitors showed excellent capacitance and energy density, highlighting the potential of small mesopores in enhancing electrode material performance.