Superior electrochemical performance of bimetallic sulfides as electrode materials for battery supercapacitor applications

Hybrid supercapacitors have achieved much attention for their versatility in energy storage applications. But they still require better electrode materials with flashing electrochemical properties to boost their specific capacity, energy, and power limits. The improved electrical conductivity and high electrochemical activities of transition metal sulfides make them ideal contenders to be use for hybrid supercapacitor applications. In this regard, CoMnS was synthesized with different concentrations by employing a hydrothermal approach. The synergistic effect of Co0·50Mn0·50S shows optimum performance in three electrode configuration by delivering high specific capacity (Qs) of 542.8 C/g at 2.0 A/g. This electrode also shows lower series resistance during electrochemical impedance spectroscopy, confirming their better electrical conductivity. A hybrid device (Co0·50Mn0·50 S//AC) was accomplished showing intriguing properties which includes Qs of 191.8 C/g (0.4 A/g) with great cycling stability (95.02%) and rate capability. The fabricated device also results in high energy of 45.28 W h/kg with great power of 1700 W/kg. Furthermore, diffusive, and capacitive contributions were evaluated to validate our experimental outcomes. Considering these results, the as-synthesized material is a potential choice for battery-supercapacitor applications. •Bimetallic sulfides are synthesized for hybrid supercapacitor as energy storage application.•The synergistic effect of transition metals (Co and Mn) enhanced the electrochemical performance.•Electrochemical characterizations indicated the bimetallic sulfides to be more effective than single metal sulfides.