Synthesis of layered 2H–MoSe₂ nanosheets for the high-performance supercapacitor electrode material

In this work, we report the synthesis of layered 2H–MoSe₂ nanosheets via an in-situ selenization route and investigated their electrochemical charge storage performance. The structure and morphology of the as-synthesized samples have been investigated systematically. The electrochemical performance of the MoSe₂ nanosheets towards the supercapacitor has been probed by a three-electrode cell configuration in 2 M KOH electrolyte solution. The prepared MoSe₂ nanosheets show excellent electrochemical performance with a specific capacity of 46.22 mAh g⁻¹ at a current density of 2 Ag^-1. The MoSe₂ electrode exhibit remarkable cyclic stability up to 2000 charge-discharge cycles. In addition, the fabricated MoSe₂ symmetric supercapacitor delivered a specific capacitance of 4.1 Fg^-1 at a current density of 0.5 Ag^-1. It exhibited high cyclic stability with capacitance retention of 105% and high coulombic efficiency of 100% even after 10000 cycles. The high specific capacity and good cyclic stability of the MoSe₂ nanosheets suggest its application as an efficient electrode material for electrochemical supercapacitor.