Xueying Cao, Xiaoxia Wang, Liang Cui
Nov 1, 2017
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Influential Citations
55
Citations
Journal
Chemical Engineering Journal
Abstract
Abstract Herein, we report the preparation of strongly coupled nickel boride/reduced graphene oxide (Ni2B/RGO) hybrid via simultaneous chemical reduction of nickel dichloride (NiCl2·6H2O) and graphene oxide (GO) in one pot using NaBH4 as reductant under nitrogen atmosphere. The Ni2B/RGO hybrid is demonstrated to be an excellent and novel electrode material for supercapacitors. The specific capacitance of Ni2B/RGO hybrid annealed at an optimized temperature of 200 °C (Ni2B/RGO-200) can reach 1073.4 F g−1 at a current density of 1 A g−1 in 6 M KOH solution. Meanwhile, the hybrid supercapacitor (HSC) device fabricated using Ni2B/RGO-200 as positive electrode and activated carbon (AC) as negative electrode delivers a high energy density of 22.1 Wh kg−1 at a power density of 724.9 W kg−1. After 2500 charge-discharge cycles at a current density of 6 A g−1, the HSC can still retain 72.4% of its initial performance. The excellent capacitor performance of Ni2B/RGO-200 hybrid should not only attribute to the adequate electrochemical reaction active sites of Ni2B particles, but also the enhanced electron transfer rate and superior electrochemical stability of graphene.