2H–MoS2 nanoflowers based high energy density solid state supercapacitor

Abstract

Metal dichalcogenides nanostructures are observed as suitable materials for storage applications. Herein, we report three dimensional MoS2 nanoflowers with hexagonal (2H) phase for supercapacitor application. The 2H–MoS2 nanoflowers based supercapacitor electrodes exhibit a high specific capacitance of 382 Fg-1 at a current density of 1 Ag-1 in three electrodes measurements with 1 M Na2SO4 aqueous electrolyte. The symmetric solid state supercapacitor device with 2H–MoS2 nanoflowers electrodes and PVA-Na2SO4 electrolyte exhibits an outstanding cell performance with an energy density of 16.4 Wh kg−1 (measured at a constant current density of 0.2 A g−1) and an excellent capacitance retention of 97.5% after 4000 cycles. The outstanding performance of 2H–MoS2 nanoflowers based electrodes can be attributed to the 3D flower like architecture with large number of exposed edges of different petals and their wettability due to oxygen containing functional groups. © 2020 Elsevier B.V.