Chitosan-derived hybrid porous carbon with the novel tangerine pith-like surface as supercapacitor electrode

A novel hybrid porous carbon has been synthesized by a facile method blending chitosan with gelatin in acetic acid solution. Gelatin changes the morphology of the chitosan-derived carbon materials and produces abundant micro- and mesopores with the help of KHCO3. More importantly, gelatin brings heteroatoms and pseudo-capacitance into hybrids to improve the capacitive performance as the nitrogen source. A unique tangerine pith-like morphology comes into being on the chitosan-derived hybrid porous carbon, and there are lots of interconnected micropores forming with high specific surface area of 927.17 m2 g−1. This particular morphology, high nitrogen content and specific surface area ensure the as-obtained carbon electrode wonderful capacitive performance with specific capacitance of 331 F g−1 in 6 mol L−1 KOH electrolyte at 1 A g−1, high retention of 73% and excellent capacity stability of 90% after 10000 cycles at 10 A g−1. Additionally, the chitosan-derived hybrid porous carbon shows remarkable energy density of 34 W h kg−1 with the power density of 900 W kg−1, superior to majority of the commercial devices. The simple and efficient strategy and the excellent electrochemical performance are of great significance to the large-scale application of biomass-based supercapacitors.