Nitrogen-doped amorphous carbon-silicon core-shell structures for high-power supercapacitor electrodes.

摘要: We report successful deposition of nitrogen-doped amorphous carbon films to realize high-power core-shell supercapacitor electrodes. A catalyst-free method is proposed deposit large-area stable, highly conformal and conductive (a-C:N) by means a direct-current plasma enhanced chemical vapor technique (DC-PECVD). This approach exploits C2H2 N2 gases as the sources nitrogen constituents can be applied various micro nanostructures. Although as-deposited a-C:N have porous surface, their porosity significantly improved through modification process consisting Ni-assisted annealing etching steps. The electrochemical analyses demonstrated superior performance modified active material, where specific capacitance densities high 42 F/g 8.5 mF/cm2 (45 F/cm3) on silicon microrod arrays were achieved. Furthermore, this electrode showed less than 6% degradation over 5000 cycles galvanostatic charge-discharge test. It also exhibited relatively energy density 2.3 × 103 Wh/m3 (8.3 × 106 J/m3) ultra-high power 2.6 × 108 W/m3 which among highest reported values.