Hierarchical CoGa layered double hydroxides grown on nickel foam as high energy density hybrid supercapacitor

Abstract

Hierarchical cobalt gallium layered double hydroxide microns flower and sheet was in situ gown on Ni foam via a facile and one-step hydrothermal method. The capacity of preparing Co-Ga-layered double hydroxides (Co-Ga-LDH), as supercapacitor electrode, was evaluated via three electrode system. And different feeding ration of cobalt and gallium was attempted to optimize the better capacity performance. The as-obtained Co-Ga (1:1)-LDH hybrid shows the enhanced the specific capacity 1431.5 C/g at current density of 1 A/g and approximately 74% initial capacity at current density of 20 A/g. A hybrid supercapacitor was assembled consisting of Co-Ga-LDH and reduced graphene (rGO), which show the high energy density 68.07 Wh/kg at power density 825 W/kg. To our best knowledge, it is the first time that cobalt gallium layered double hydroxides was prepared and studied in energy storage field.