Controlled Electrochemical Growth of Spinel NiCo2S4 Nanosheets on Nickel Foam for High Performance Supercapacitor Applications

Abstract

Spinel metal oxides/sulfides possess higher reversible capacity, better electronic conductivity and have been investigated for high performance electrode materials for supercapacitors. Herein, we report a facile, low-cost and one-step electrodeposition approach for the synthesis of thin film NiCo2S4 (NCS) nanosheet arrays on Ni foam substrate. The elemental composition and morphology of the materials are characterized by energy dispersive x-ray analysis and field-emission scanning electron microscopy. The supercapacitor performance of the NCS nanosheets are studied in three electrode configuration in 2M KOH electrolyte. The as-prepared binder free electrode showed a high specific capacitance of 1500 F/g at 3 A/g with excellent cycling stability even after 1000 charge/discharge cycles. Obtained energy density and power density of the NCS nanosheets are 50.58 Wh/Kg and 12.978 Kw/Kg respectively. The superior electrochemical performances are mainly attributed to its nanosheet like structure which provides large reaction surface area, fast ion and electron transfer rate. � 2018 Elsevier Ltd.