The microwave synthesis of porous CoSe2 nanosheets for super cycling performance supercapacitors

Abstract

Porous CoSe₂ nanosheets prepared via a one-step microwave method can be considered an excellent electrode material and the associated electrochemical properties were evaluated. The porous CoSe₂ nanosheets revealed admirable electrochemical properties in terms of high specific capacitance (333 F g⁻¹ when the current density is 1 A g⁻¹) and excellent enduring stability (100.97% of the initial specific capacity over 25 000 cycles at 5 A g⁻¹). An asymmetric supercapacitor (CoSe₂-anode, AC-cathode) was assembled, offering good properties accompanied by an energy density of 18.9 W h kg⁻¹ when the power density reached 387 W kg⁻¹. These impressive results are obtained largely on account of the porous structure of CoSe₂, which provides a path for ion transport, and the introduction of Se into CoSe₂, which offers high electrical conductivity, further enhancing the electrochemical performance.