One-Step Solvothermal Synthesis of 3D Hierarchical Ni x Co9-x S8 Structures for High-Performance Supercapacitors

Facile one-pot synthesis of NiCo2Se4-rGO on Ni foam for high performance hybrid supercapacitors

A facile, innovative synthesis for the fabrication of NiCo₂Se₄-rGO on a Ni foam nanocomposite via a simple hydrothermal reaction is proposed. The as-prepared NiCo₂Se₄-rGO@Ni foam electrode was tested through pxrd, TEM, SEM, and EDS to characterize the morphology and the purity of the material. The bimetallic electrode exhibited outstanding electrochemical performance with a high specific capacitance of 2038.55 F g⁻¹ at 1 A g⁻¹. NiCo₂Se₄-rGO@Ni foam exhibits an extensive cycling stability after 1000 cycles by retaining 90% of its initial capacity. A superior energy density of 67.01 W h kg⁻¹ along with a high power density of 903.61 W kg⁻¹ further proved the high performance of this electrode towards hybrid supercapacitors. The excellent electrochemical performance of NiCo₂Se₄-rGO@Ni foam can be explained through the high electrocatalytic activity of NiCo₂Se₄ in combination with reduced graphene oxide which increases conductivity and surface area of the electrode. This study proved that NiCo₂Se₄-rGO@Ni foam can be utilized as a high energy density-high power density electrode in energy storage applications.

A hybrid supercapacitor comprising a NiCo₂Se₄-rGO composite has been fabricated on Ni foam and shows high energy and power density and superior flexibility.