MnCoOx-multi-walled carbon nanotubes composite with ultra-high specific capacitance for supercapacitors

Spherical MnCoOx and MnCoOx-multi-walled carbon nanotubes (MnCoOx-MWCNTs) were synthesized by hydrothermal method, and applied as electrode materials for supercapacitors. Cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), electrochemical impedance spectroscopy (EIS) and other electrochemical test methods are used to screen the properties of MnCoOx with different Co/Mn molar ratios and MnCoOx-MWCNTs with different MWCNTs qualities. The performance comparisons show that when the molar ratio of Co/Mn was 1:1, the discharge capacitance of as-prepared MnCoOx-MWCNTs composite containing 0.1 g MWCNTs is as high as 930.00 F g−1 at the current density of 1.0 A g−1. The retention rate of specific capacitance of optimal MnCoOx-MWCNTs remains 88.2% after 5000 cycles at the current density of 8.0 A g−1. Therefore, MnCoOx-MWCNTs composite as electrode material has broad development prospects.