Novel chemical route for synthesis of CeO2–ZnO nanocomposite towards high electrochemical supercapacitor application

Abstract

Herein, CeO2–ZnO nanocomposite was synthesized by a simple chemical precipitation method. The crystallite size and structure of composite were investigated using X-ray diffraction spectroscopy (XRD). The morphology and actual size of nanocomposite are determined using scanning electron microscopy (SEM) and high-resolution electron microscopy (HR-TEM), revealing mono-dispersed spherical-shaped articles with size of ~ 5 nm. Optical and magnetic properties of composite were examined by UV–Vis, PL and EPR studies. The electrochemical supercapacitor performance of CeO2–ZnO nanocomposite was employed by cyclic voltammetry (CV) and galvanostatic charge–discharge (GCD) and impedance spectroscopy (EIS). The highest specific capacitance of 424 Fg−1 at scan rate of 5 mVs−1 from CV and 377 Fg−1 at current density of 1 Ag−1 from GCD was achieved. High capacitance retention of 94.6% was attained at the current density of 1 Ag−1. This work demonstrates that good reversibility, better rate capability and long-term stability of CeO2–ZnO composite electrode were applicable in wide-range potential applications.