Durable, Rate Capable and High Energy Hybrid Supercapacitor from PANI/ZnO/SnO2 Nanocomposite with Zero-Waste Electrolyte Approach

Abstract

A hybrid supercapacitor material, polyaniline/ZnO/SnO2 of weight percentages of 58.34%: 8.33%:33.33% (PZnSn), respectively, was synthesized in a facil in-situ single-step method. Remarkably, the constituent ZnO was synthesized at 90 °C in an in-situ single-step method along with two other constituents in 2 hrs. The astonishment is due to the point that the synthesis of ZnO generally involves calcination at high temperatures for a longer duration. The energy storage performance was evaluated with two aqueous electrolytes, viz., 1 M H2SO4 (SA) and the liquid by-product that was obtained after the synthesis of PANI (SLP). The SLP provided 57.25% higher energy storage performance in relation to that provided by the SA. The PZnSn exhibited a durable and rate-capable energy storage property by exhibiting robustness up to 16,500 cycles at 0.4 V s‒1 and 39 A g‒1, respectively, in the presence (ITP) of SA and up to 15,000 cycles at 0.4 V s‒1 and 42 A g‒1 ITP of SLP, respectively, in a real-time symmetric two electrode systems. The PZnSn displayed a remarkable trait of enhancement of energy storage with an increase in the number of charge and discharge cycles ITP of both the electrolytes. However, the enhancement provided by SLP is higher than that of SA. The maximum performance achieved from PZnSn ITP of SLP is a Q of 347.2 C g‒1, an E of 57.87 W h kg‒1 (comparable with Ni-Cd batteries) and a P of 1.2 kW kg‒1 at 1 A g‒1.