MoO2/mesoporous carbon and MoO2/reduced graphene oxide composite electrodes for supercapacitor applications

Abstract

The electrochemical properties of MoO2/mesoporous carbon and MoO2/reduced graphene oxide (rGO) materials have been investigated. Composite materials have been obtained by ultrasound dispersion of hydrothermally synthesized MoO2 and carbon or rGO (mass ratio of 1:1 and 1:2). The samples have been tested using XRD, SEM, and low-temperature nitrogen adsorption–desorption. The electrochemical performance was investigated by cyclic voltammetry and galvanostatic cycling methods. The maximal specific capacitance values for MoO2/carbon (1:1) and MoO2/carbon (1:2) materials are 225 and 120 F/g, respectively. It is the evidence that increase in carbon content causes specific capacitance decreasing. For the case of MoO2/reduced graphene oxide (1:1) material the maximal value of the specific capacitance is 52 F/g that is less than one for pure MoO2. An increase in reduced graphene oxide content causes the increase in specific capacitance value up to 232 F/g that corresponds to the decrease in MoO2 average particle sizes and contribution of reduced graphene oxide component to pseudocapacitance response.