CoSe/NC Composites through the Selenization of ZIF-67 for High-Performance Supercapacitor Electrodes

ZIF-based electrode materials are considered to be efficient electrode materials for supercapacitor applications because of their adjustable structure and greater surface area features. In this work, CoSe/NC (nanoporous carbon) composites were synthesized by keeping the mass ratio of ZIF-67 constant and varying the amount of selenium powder, pyrolyzed at 800 °C under a reducing atmosphere(Ar/H2) for 4 h. ZIF-67 was synthesized by the coprecipitation method. CoSe-1 showed excellent electrochemical performance with the highest value of specific capacitance (746 F g–1 at 2 mV s–1), showing a cyclic capability of 82.3% after 4000 cycles because of the optimized ratio of cobalt and selenium in it.