Abstract
NiCo-phosphates can deliver high specific capacitances and high electrochemical activities as pseudoca-pacitive electrode material for supercapacitors.In this study,The NiCo-phosphates@reduced graphene oxide (NCPO@rGO) composite is directly loaded on Ni foam by a simple one-step hydrothermal process.The conductive rGO sheets provides continuous electron pathways between NCPO flowers and Ni foam,allowing active electrochemical reactions throughout the whole electrode.This can solve the difficulty of low active material utility and small areal capacitances in the Ni foam-supported electrodes.At the same time,the rGO sheets creates large amount of mesopores within the electrode,which can ensure a highly open structure for electrolyte attachment and ion transport.Because of the positive effect of rGO in improving charge transfer,the NiCo-phosphates can be fully involved in the electrochemical reactions with high utility,ensuringhighspecificcapacitances(1416.7Fg-1 at 1 Ag-1)andhigh-rateperformances.Specially,the areal capacitance of the NCPO@rGO electrode can reach as large as 3.69F cm-2 at 1 A g-1,which is among the highest ones in Ni foam supported electrodes.An asymmetric supercapacitor is then fabricated by NCPO@rGO as the positive material with attractive energy densities and power densities,further proving its excellent electrochemical performance.
基金项目
Fundamental Research Funds for the Central Universities of China(2652018291)
Fundamental Research Funds for the Central Universities of China(2652018318)
NETL
NSTL
万方数据