Hierarchical nanostructured Au–SnO2 for enhanced energy storage performance

Abstract

Electrode materials with high energy and power density are mostly essential to overcome traditional fossil fuel use. Herein, we demonstrate the synthesis of Au decorated self-assembled SnO2 nanoflowers consisting of nanorods by a cost-effective and eco-friendly solvothermal process. The as-synthesized SnO2 based materials were employed as electrode material in the energy storage system, which delivered considerably high specific capacitance of 634.3 F/g at a current density of 1 A/g. The electrode material also exhibits excellent cycle stability of 83.52% after 4000 galvanostatic charge–discharge (GCD) cycles. The high specific capacitive value is attributed to the hybrid performance of battery and supercapacitor, more active sites, and higher surface area. A solid state asymmetry device was fabricated using Au–SnO2 and activated carbon (AC) as positive and negative electrodes. The asymmetry device shows an excellent energy density of 168.9 Wh/kg at a power density of 1 kW/kg with an applied current density of 1 A/g.