Dandelion-Like CuCo2O4 Arrays on Ni Foam as Advanced Positive Electrode Material for High-Performance Hybrid Supercapacitors

Abstract In this paper, CuCo2O4 dandelion arrays grown on nickel foam (CuCo2O4/NF) was successfully synthesized by a simple hydrothermal route with post-heat-treatment for emolying as a high-performance positive electrode material for hybrid supercapacitors. Due to the unique tree-dimension porous (3D) microstructure and binder-free electrode architecture, the CuCo2O4/NF electrode deliveries a large specific capacitance of 2656.7 F g-1 at an areal current density of 1 mA cm-2. Moreover, it has an outstanding rate performance, as well as striking cycling stability. Additionally, a hybrid supercapacitors (HSCs) was fabricated using CuCo2O4 as positive electrode and corals-like N-doping porous carbon (N-CCs) as negative electrode. The device exhibited a broad potential window of 1.55 V and a high specific capacitance of 273.9 F g-1, which result in a largest energy density of 91.4 Wh kg-1 and a maximum power density of 13.4 kW kg-1. Finally, the assembled device manifests a preeminent electrochemical stability which maintained a 92.32 % capacitance retention after 5000 cycles. The practical application was visually validated by lighting a blue light-emitting diode.