Selenization of ZIF-67 as Electrode Material for Supercapacitor Application /

Abstract

ZIF-based materials are considered efficient electrodes for supercapacitor applications because of their adjustable structure and greater surface area features. CoSe/NC based composites have recently gained significant attention as high-performance electrode materials for supercapacitor applications. These composites typically consist of CoSe nanoparticles integrated with nitrogen-doped carbon (NC) matrices, which exhibit excellent electrochemical properties such as high specific capacitance, good rate capability, and long-term cycling stability. In this work, CoSe/NC composites were synthesized by using Selenium powder and ZIF-67, ZIF-67 being prepared from coprecipitation method using cobalt nitrate hexahydrate and 2- methyl imidazolate, the purple-colored precipitates of ZIF-67 obtained at the end of reaction were then grounded after that,by keeping the mass ratio of ZIF-67 constant and the amount of Selenium powder is varied, pyrolyzed at 800 °C under a reducing atmosphere(Ar /H2) for 4 hours, XRD was done for all the three prepared electrodes showing the successful formation of CoSe .SEM analysis showed nanoporous morphologies of CoSe composites of all the prepared samples annealed at 800 °C . The highest degree of graphitization in the case of CoSe-1 could be assigned to better electrochemical performance. The CoSe-1 showed excellent electrochemical performance with the highest value of specific capacitance (746F g-1-1at 2mVs), showing a rate capability of 82.3% after 4000 cycles because of optimize ratio of Cobalt and selenium in CoSe-1. Overall, CoSe/NC based composites CoSe-1 showed a promising avenue for the development of high-performance electrode materials for supercapacitor applications.