Ni Catalytic Graphitized Porous Carbon As Electrode Material for High Performance Supercapacitors

Whey protein derived, N-doped porous carbon has been prepared by preliminary carbonization at 400  and final KOH activation at 700  combined with catalytic graphitization. Physical characterization, indicated the obtained N-doped activated electrode material exhibited a large specific surface area (2536.2 m² g^-1) and plenty of interconnected cavities, which greatly improved the performance as a supercapacitor. Electrochemical measurements demonstrated that the as-prepared activated electrode material achieved exceptionally high capacitance of 248 F g^-1 at charge/discharge current density of 0.1 A g^-1. Moreover, the as-prepared activated electrode material exhibited ideal capacitive behavior with almost no capacitance loss in 6 mol L^-1 KOH at different charge/discharge current densities ranging from 0.1 to 5 A g^-1 after 1,000 charge/discharge cycles. These results suggested that biomass derived porous carbon is a promising supercapacitor electrode material.