Battery-like supercapacitor electrodes utilizing porous hierarchical bush-like ZnO/SnS on nickel foam framework

Abstract

This paper reports the electrochemical activity of mesoporous bush like ZnO/SnS nanocomposites, with a specific capacity of 523.60 C g−1, at a current density of 1 A g−1, which is higher than the specific capacities offered by pristine SnS (301.15 C g−1) and ZnO (32.67 C g−1) electrodes. The ZnO/SnS composite electrode exhibits a greater energy density of ~36.36 Wh kg−1with a power density of 250 W kg−1. The composite electrode has a cyclic stability with 56 % capacity retention for over 3500 cycles. The enhanced electrochemical performance of ZnO/SnS composite structure is attributed to its bush like morphology with a large surface area (204.4 m2 g−1) which provides a greater number of electro-active sites for the absorption of ions that leads to efficient charge transportation pathways. This type of morphology is attained only when the orthorhombic SnS nanoflakes are grown over hexagonal ZnO nanoparticles, by surfactant free homogenous precipitation method. These results demonstrate that ZnO/SnS composite is an emerging electrode material for supercapacitor application.