Fabrication of tin oxide @ graphitic carbon nitride quantum dot nanocomposite as an electrode material for supercapacitor application

Abstract

Carbon quantum dot nanoparticles enticed recent researchers with their remarkable application potential as a high-performance supercapacitor device. In this paper, on account of its low cost and non-toxicity of SnO₂ metal oxide, it is embedded with graphitic carbon nitride quantum dots (CNQDs) for supercapacitor application. One pot hydrothermal method is utilized to synthesize SnO₂/CNQDs nanocomposite (Sn-CN NC) materials. The structural and constituents of chemical present in the synthesized samples were studied by XRD, FTIR and Raman. In XRD, the tetragonal rutile structure of SnO₂ is compatible with Sn-CN NC without any additional peaks. The presence of functional groups was confirmed by the FTIR spectrum and the presence of D and G bands confirms the presence of CNQDs in Sn-CN NC in the Raman spectrum. The chemical composition and oxidation state were further analyzed by the XPS spectrum. The sphere-like morphology was observed in FESEM and HR-TEM. The HR-TEM further confirms the crystallinity of the Sn-CN NC by the SAED pattern. The weight percentage of Sn-CN NC was observed from the EDS spectrum. The electrochemical analysis of the prepared nanocomposite was investigated using CV, GCD and EIS spectrum. The Sn-CN NC delivers a high specific capacity of 314.8C/g at a current density of 1 A/g. The Sn-CN NC//AC device shows maximal energy and power density of about 72.32 Wh/Kg and 5624 W/Kg. The fabricated device has good retention of cyclic stability and coulombic efficiency. For good electrochemical performance of Sn-CN NC, this optimized NC electrode is a potential candidate in energy storage applications.