Low temperature graphitization and electrochemical properties of porous carbon catalyzed with bimetal Ni-Mo

Graphitization of porous carbon at low temperature has always been an extremely challenging problem without destroying its porous structure. In this study, the porous graphite carbon is successfully prepared through sawdust as a carbon source and bimetal nickel and molybdenum as the catalyst at the temperature of 750 °C. The results show that the graphitization degree of catalyzed porous carbon by bimetallic nickel and molybdenum increased by 9.4% compared with that of porous carbon prepared without catalyst. Nitrogen adsorption and desorption analysis show that the structure of the porous graphite carbon is dominated by 1–2 nm micropores with few mesopores. The porous graphite carbon exhibits a high specific capacitance of 267 F g−1 at 1 A g−1. The rate performance of such porous graphite carbon reaches 77.2% at 10 A g−1, which increased by 34.7% compared with that of the porous carbon obtained by the metal-free catalyst. The assembled symmetric supercapacitor displays a remarkable energy density of 19.8 Wh kg−1 at a power density of 452.9 W kg−1 in Na2SO4 electrolyte. Additionally, the device exhibits a long-term cycling stability with a 94.8% retention rate after 10,000 cycles. This study not only provides a new route for preparing porous graphitized carbon without destroying the porous structure, also gives a new choice for preparing porous carbon with high rate performance as an electrode of supercapacitor.