Self-Supported Binder-Free Hybrid Electrodes of Cu@CuO Nanowires/Carbon Nanotubes for Supercapacitors with Ultrahigh Areal-Capacitance

To meet the requirement of clean and efficient energy storage system for practical applications, supercapacitors (SCs), which are promising candidates for the next-generation energy storage devices, have received tremendous attention. Herein, a hybrid electrode consisting of copper nanowires (Cu NWs) and carbon nanotubes (CNTs) is prepared by simple vacuum-filtration method. Both Cu NWs and CNTs have excellent conductivities, high aspect ratios, and large surface areas, in which the two kinds of materials are evenly dispersed and are entangled with each other. The electrochemical performance characterization of the Cu@CuO NWs/CNTs hybrid electrode shows high specific capacitance of 1.7 F cm⁻² and excellent cycling characteristics of 97.4% after 5000 cycles. The hybrid electrode of Cu@CuO NWs/CNTs with one-dimensional (1D) structure provides significant advantages in terms of electron/ion transport pathways. The SC devices with excellent electrochemical performance and stability clearly demonstrate their broad applications as low-cost, high-performance power supplies for electronic devices.