Supersonically Sprayed Zn2SnO4/SnO2/CNT Nanocomposites for High-Performance Supercapacitor Electrodes

Abstract

In this study, we demonstrate rapid and facile supersonic cold spray deposition of Zn2SnO4/SnO2/CNT nano-composite supercapacitor electrodes with promising combinations of power and energy density. Cyclic voltammetry confirmed the capacitive behavior of the optimized electrode, with specific capacitance reaching 260 F.g(-1) at a current density of 10 A.g(-1). We attribute this high performance to the optimal combination of CNT (carbon nanotube; double-layer capacitance) and Zn2SnO4/SnO2 (pseudocapacitance) properties. The mesoporous and accessible surface of the CNT significantly contributed to the excellent retention (approximately 93%) of the specific capacitance after 15000 galvanostatic charge/discharge cycles. In addition, the supercapacitor exhibited a remarkable energy density, electrochemical properties, and mechanical stability. The materials and approach presented here can enable