Self-templated one-step hydrothermal synthesis of hierarchical actinomorphic flower-like SnO2-ZnO nanorods for high-performance supercapacitor application

In this paper, we demonstrate the unique actinomorphic flower-like morphology of a tin oxide -zinc oxide (SZ) nanocomposite that has been synthesized using a one-step hydrothermal method and investigated for supercapacitor (SC) application. The optical, morphological and elemental composition features of pure SnO2 and SZ nanocomposite were carried out by using different characterization techniques such as XRD, FTIR, FESEM, HRTEM, and XPS. The SZ-10 nanocomposite was the most significant one and was used in the fabrication of all solid-state symmetric supercapacitor. Electrochemical analysis of the Galvano charging-discharging (GCD) curves achieved a high specific capacitance (Csp) of 797.23 Fg−1 at a current density (CD) of 1 Ag−1. The cyclic voltammetry (CV) curve for the SZ-10 electrode shows the high Csp of 548.56 Fg−1 at a scan rate of 10 mV/s. It has superior cyclic stability with capacitance retention of 88.2% and coulombic efficiency of 98.7%, even after 5000 repetitive cycles. The SZ-10 electrode also shows a high energy density (ED) of 45.72 Whkg−1 and a power density (PD) of 406 Wkg−1, at a CD of 1 Ag−1. Furthermore, the fabricated SC device is linked in series to turn on a commercial red LED that glows for 1 to 2 min. These investigations demonstrate that the SZ-10 nanocomposite is an excellent electrode material for high-energy storage devices for SC applications.