In situ N, O co-doped porous carbon derived from antibiotic fermentation residues as electrode material for high-performance supercapacitors

With the widespread use of antibiotics, the safe utilization of waste antibiotic fermentation residues has become an urgent issue to be resolved. In this study, in situ N, O co-doped porous carbon was prepared using fresh oxytetracycline fermentation residue under the mild activation of the green activator K(2)CO(3). The optimal sample exhibited a 3D grid carbon skeleton structure, excellent specific surface area (S(BET) = 948 m(2) g(−1)), and high nitrogen and oxygen content (N = 3.42 wt%, O = 14.86 wt%). Benefiting from its developed morphology, this sample demonstrated excellent electrochemical performance with a high specific capacitance of 310 F g(−1) at a current density of 0.5 A g(−1) in the three-electrode system. Moreover, it exhibited superior cycling stability with only a 5.32% loss of capacity after 10 000 cycles in 6 M KOH aqueous electrolyte. Furthermore, the symmetric supercapacitor prepared from it exhibited a maximum energy density of 7.2 W h kg(−1) at a power density of 124.9 W kg(−1), demonstrating its promising application prospects. This study provided a green and facile process for the sustainable and harmless treatment of antibiotic fermentation residues.