Biomass carbon–modified CoZn/C as a high-performance electrode for supercapacitors

In this study, biomass carbon–modified CoZn-ZIF-8 was firstly fabricated through a hybridization approach. The CoZn/C was prepared by directly carbonizing a CoZn-ZIF-8/C at the designed temperature and investigated by multiple techniques including XRD, XPS, SEM, and TEM analyses. After carbonization, CoZn/C shows a high capacitance of 757.8 F/g at 5 mV/s, which is an outstanding characteristic compared with that of recently reported supercapacitor. As a consequence, the improved electrochemical performance of CoZn/C attributed to the biomass carbon can significantly enhance the mass transport channels of electron-hole pairs. Remarkably, the composite shows excellent capacitive performances originating from the abundant reservoir for the charge storage derived from ZIF-derived porous and electroactive species exposure as well as high ion diffusion rate. CoZn/C can be regarded as a promising material for practical supercapacitor, and this work also provides a valuable reference for the preparation and application of high-performance electrode materials which greatly promote the supercapacitor development.