Synthesis and analysis of the impact of rGO on the structural and electrochemical performance of CoMnS for high-performance energy storage device

Abstract

Two-dimensional (2D) materials have considered a lot of attention because of their high conductivity and storage capability. In the present work, the rGO (reduced graphene oxide) and cobalt manganese sulfide (CoMnS) nanostructures are synthesized using the modified Hummer's and hydrothermal approaches, respectively and measured the structural and electrochemical properties. The rGO@ CoMnS composite electrode material has a superior specific capacity of 1355.8 C/g compared to the reference electrode (747.6 C/g) at 1.8 A/g in 3-electrode measurement systems. The estimated specific capacitance is 2238 F/g at 1.8 A/g. The charge storage mechanisms are supported with the help of Randles–Ševčík and Dunn’s models. Besides, the rGO@CoMnS@AC composite electrodes are used to design a hybrid device (supercapattery). The hybrid-type device displays an exceptional power density of 2880 W/kg and a notable energy density of 45.6 W h/kg. The electrode is measured up to 5000 cycles and measured the capacity retention of 88% with 91% of columbic efficiency. The two-dimensional composite electrodes provide new opportunities to design a high-performance energy devices.