Three-dimensional flower-like nanocomposites based on ZnO/NiO as effective electrode materials for supercapacitors

Official URL: https://dx.doi.org/10.1016/j.jelechem.2023.117158

The efficient hybrid materials with high specific capacity and long stability are highly desirable electrode materials for supercapacitors. Herein, composites based on ZnO/NiO as active electrode materials was fabricated using soft-templated hydrothermal method. The NiO and ZnO were successfully synthesize into 3D flower structures. The as-synthesized ZnO and NiO were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The electrochemical measurements of the fabricated ZnO/NiO electrodes were carried out by series of cyclic voltammetry (CV), galvanostatic charge–discharge (GCD) and electrochemical impedance spectroscopy (EIS). The highest specific capacity of 350 C g−1 was found at 2 A g−1 current while the lowest specific capacity of 217 C g−1 was measured at 20 A g−1. Finally, the 3D flower-shaped ZnO/NiO electrode revealed cyclic stability of 72.1 % capacitance retention and 97.1 % Coulombic efficiency at the end of 8000 GCD cycles. The current study revealed augmented supercapacitor properties with exceptional cyclic stability of ZnO/NiO composite-based electrodes.