All transition metal selenide composed high-energy solid-state hybrid supercapacitor

Abstract

There is disclosed a method and a system for a versatile in-situ approach to design the nanostructured transition metal selenide (TMS) materials for the high-energy solid-state hybrid supercapacitors (HSCs). Initially, the rose-nanopetals like NiSe@Cu2Se (NiCuSe) cathode and FeSe nanoparticles anode are directly anchored on 3D highly conducting Cu foam via purposefully in-situ conversion reactions. The different potential windows of the NiCuSe and FeSe in aqueous electrolytes associated with the excellent electrical conductivity and redox activity results in the superior electrochemical features for the half cell with maximum specific capacity of 534.2 mA h g−1 for NiCuSe and 573.8 mA h g−1 for FeSe at current density of 1 A g−1, respectively. The solid-state HSC cell with NiCuSe cathode and FeSe anode delivers a highest specific energy of 87.6 Wh kg−1 and excellent cycle lifetime with capacity retention of 91.3% over 10,000 cycles.

Dependencies are inferred from the claim text.