Electrodeposited nickel aluminum-layered double hydroxide on Co3O4 as binder-free electrode for supercapacitor

Abstract

Here, we report a heterostructured core-shell electrode consists of cobalt oxide (Co3O4) nanowire core and nickel aluminum (NiAl)-layered double hydroxide (NiAl-LDH; herein Co3O4@LDH) nanosheet shell grown on nickel foam as advanced electrode for supercapacitor. Benefiting from the core-shell configuration and smart hybridization, the optimized Co3O4@LDH core-shell electrode exhibits a high capacitance of 2011Fg(-1) at 2Ag(-1) and remains 1455Fg(-1) at 40Ag(-1), which outperforms the electrochemical performance of individual component of Co3O4 (720Fg(-1) at 2Ag(-1)). A hybrid supercapacitor using Co3O4@LDH as positive electrode and carbon nanotube as negative electrode delivers an energy density of 18.1Whkg(-1) at a power density of 375kWkg(-1) at a current density of 0.5Ag(-1). Smart hybridization of core-shell electrode shows great promise as advanced electrode materials for supercapacitor with high electrochemical performance.