Waste bio-tar based N-doped porous carbon for supercapacitors under dual activation:performance,mechanism,and assessment

Bio-tar extra-produced from biomass pyrolysis is prone to pose a threat to environment and human health.A novel N-doped porous electrode from bio-tar was produced under dual-activation of urea and KOH in this study.Onepot dual-activation played significant roles in N-functional group and micro-mesoporous structure,which resulted in the carbon material with the highest of nitrogen content(4.08%)and the special surface area(1298.26 m^(2)·g^(−1)).Specifically,the potential mechanisms of pore formation and N-doping in the one-pot dual-activation strategy were also proposed as a consequence,the one-pot dual-activated carbon material displayed excellent electrochemical performance with the highest capacitance of 309.5 F·g^(−1) at 0.5 A·g^(−1),and the unipolar specific capacitance remained with cyclic characteristics of 80.1%after 10,000 cycles in two-electrode symmetric system.Furthermore,the one-pot dual-activation strategy could create a profit of$1.64-$2.38 per kilogram of bio-tar processed without considering the initial investment and labor costs,which provides new perspectives for the utilization of waste bio-tar.