CuO@NiCo-LDH core-shell structure for flexible fiber-shaped supercapacitor electrode material

Abstract

Metal fiber electrodes are of great interest for their excellent electrical conductivity and flexibility, however the limited surface area is unfavorable for the electrochemical performance. Herein, CuO nanowires in-situ growth on one dimensional (1D) Cu wire were obtained by wet chemistry and annealing method, and NiCo-LDH nanoplates were further growth on CuO nanowires by hydrothermal method to fabricate CuO@NiCo-LDH. The combination of CuO nanowires and NiCo-LDH nanoplates creates a three-dimensional (3D) core-shell structure, which improves the specific surface area and the electrochemical properties. In addition, there is a synergistic effect between the highly reactive of NiCo-LDH and the well-conducting of CuO/Cu. The composite presents a high specific capacitance of 1220.4 mF cm−2 at 1 mA cm−2. Moreover, the CuO@NiCo-LDH//activated carbon paper (ACP) asymmetric supercapacitor exhibits an excellent energy density of 20.1 μWh cm−2 at the power density of 556.3 μW cm−2, outstanding cycling stability with specific capacitance retention of 87.1 % after 6000 cycles and good bending performance. This paper provides a novel idea for the reasonable construction of electrode material structure.