Conducting polymer wrapped SnO2/RGO nanocomposite: An efficient high-performance supercapacitor material

Abstract

This study describes a ternary poly (3,4-ethylenedioxythiophene)-poly-(styrenesulfonate) (PEDOT:PSS)-wrapped tin oxide/reduced graphene oxide (SnO2/RGO/PEDOT: PSS) (SGP) nanocomposite electrode as a supercapacitor electrode. The properties of the SGP nanocomposites were studied using various characterization techniques such as X-ray Diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy (TEM), Raman spectroscopy, and electrochemical impedance spectroscopy. The XRD results demonstrated the reduction of graphene oxide during the synthesis. TEM analysis confirmed the presence of PEDOT: PSS and graphene layers adorned with minuscule SnO2 particles. Standard three-electrode geometry was used to investigate the electrochemical properties of the samples. For comparison, a two-electrode system was used to investigate the electrochemical properties. The as-prepared SGP nanocomposite electrode exhibited specific capacitance of 252.0 F/g and 124 F/g at a scan rate of 1 mV/s for the three-electrode and two-electrode systems, respectively. Furthermore, the electrode retained approximately 97.8 % of its capacitance even after 5000 cycles. However, the SGP electrode when operated to wide voltage window -0.6 V to +0.6 V exhibited the maximum specific capacitance of 285.0 F/g at scan rate 1 mV/sec and shows 114 % enhancement in the capacitance retention after the 5000 cycles at current density of 10 A/g which gives a protocol for future energy storage device application with high operating voltage. The SGP-based supercapacitor exhibited a high energy density (17.7 Wh kg −1) and power density (1220 W kg −1).