Preparation and electrochemical properties of two-dimensional nanorod structure CoMn2O4/CC electrode materials

Abstract

Metal oxides are often used as electrode materials for supercapacitors because of their high capacity， low cost， suitability for commercialization， and environmental friendliness. In this study， Mn-MOF was used as a precursor and placed in ethanol for ion exchange and etching reaction with Co（NO3）2， followed by heat treatment in air， and finally highly crystalline CoMn2O4 two-dimensional nanorod structures were obtained on a carbon cloth（CC） substrate. SEM and XRD analyses of CoMn2O4/CC prepared with different Co（NO3）2 additions and Mn2O3/CC obtained by direct heat treatment were performed， and electrochemical properties were measured by cyclic voltammetry test， constant current charge/discharge test and AC impedance test. The results show that the parent structure of CoMn2O4/CC is relatively well preserved after 0.3 g Co（NO3）2 etching， forming a nano-hollow structure， and the vertical nanorod structures grow in situ on carbon cloth after heat treatment wrapping carbon fibers uniformly and densely， ensuring high mechanical stability and electrical conductivity due to the absence of any binder addition. The electrode material has an area specific capacitance of 809.8 mF·cm-2 at the current density of 1.2 mA·cm-2 and the capacitance retention is 79.1% after 5000 cycles at the current density of 5 mA·cm-2，showing potential application prospects.

Keywords

• supercapacitor
• manganese-based metal-organic framework derivative
• electrode material
• flexibility