Nanostructured CuO/Co2O4@ nitrogen doped MWCNT hybrid composite electrode for high-performance supercapacitors

Abstract

Nanosheet-like structures of copper cobaltite (CuO/Co2O4) decorated on N-MWCNT electrodes were synthesized through hydrothermal process in the presence of ammonia/urea. The structural and morphological properties were characterized by Raman, XRD, XPS, SEM, SEM-EDX and FE-TEM analysis. The electrochemical properties of the CuO/Co2O4@N-MWCNT hybrid electrodes were studied using cyclic voltammetry, galvanostatic charge - discharge, and electrochemical impedance analyses. The prepared CuO/Co2O4@N-MWCNT and CuO@NMWCNT electrodes showed a specific capacitance of similar to 246 Fg(-1) and 100 Fg(-1) at a current density of 0.5 Ag-1 for three electrode assembly. Further, the asymmetric cells also fabricated and it delivered the highest specific capacitance of 268 Fg(-1) and 279 Fg(-1) for CuO@N-MWCNT and CuO/Co2O4@N-MWCNT electrodes respectively. These electrodes possessed very good capacitance behavior with 89% retention even after 5000 cycles at 0.5Ag(-1) which overlay a way to use as promising candidates for the high-performance supercapacitors.