Biomass Heteroatom Carbon/Cerium Dioxide Composite\nNanomaterials Electrode for High-Performance Supercapacitors

Abstract

Carbon\nmaterials have been widely used in fabricating supercapacitors.\nHowever, their capacitive performance is poor but can be improved\nby means of heteroatom doping and increasing active sites. Herein,\na green and facile strategy is introduced to synthesize a heteroatom\ncarbon/CeO₂ nanoparticles complex (HCCN-<i>x</i>, including C, N, O, and Ce elements) using a natural plant, yellow\nbean sprout, as the carbon source. According to the results, the calcination\ntemperature provides great influence on the electrochemical properties\nof HCCN-<i>x</i>. In comparison with HCCN-600 and HCCN-700,\nthe HCCN-800 electrode exhibits outstanding performance with the gravimetric\ncapacitance being up to 752 F g^–1 and the capacitance\nretention remaining 97.5% after 10 000 cycles. Besides, the\nHCCN-800 electrodes are also assembled in the symmetric supercapacitors\nwith the energy density being 25.5 Wh kg^–1. Our\nresearch opens up a novel avenue for designing of biomass carbon composites\nin energy conversion and storage utilization.