Construction of CuO@Ni–Fe layered double hydroxide hierarchical core–shell nanorods arrays on copper foam for high-performance supercapacitors

Abstract

In this work, the unique hierarchical core–shell nanorods arrays consisting of Ni–Fe layered double hydroxide (LDH) nanosheets shell and CuO nanorods core have been designed and synthesized on the copper foam substrate by two-step in situ electrochemical processes. The resulting CuO@Ni–Fe LDH electrodes can be directly used as binder-free electrodes for high performance supercapacitors, and the prepared samples revealed an improved specific capacitance (2.682 F cm−2), good coulombic efficiency of 82.7%, and long cycling lifespans. The unique structures can provide massive active sites for redox reactions, shorten the diffusion pathway for ions and improve the mechanical strength of the sample. Therefore, the CuO@Ni–Fe LDH electrode has a good potential for high performance energy storage devices.