A crucial investigation on the N, S dual-doped rGO for the electrochemical detection of mutilfarious analytes and energy storage behaviour in dual redox additives

Abstract

The dual application-based scenario in electrochemistry has gained substantial reliability and benefits across various domains. In this study, N, S dual-doped graphene (NSGO) was synthesized via hydrothermal method and utilized for supercapacitor and electrochemical sensing applications. For electrochemical sensing, the NSGO-modified glassy carbon electrode (NSGO/GCE) was used to detect 2,4-dinitrophenol (DNP), 2,4-dinitrotoluene (DNT), hydroquinone (HQ) and resorcinol (RC). The NSGO/GCE demonstrated enhanced sensing performance with low detection limits of 16 nM (DNP), 12 nM (DNT), 0.1 µM (HQ) and 0.08 µM (RC) in a linear dynamic range from 0.1 µM to 60.0 µM (DNP, DNT) and 1.0 µM to 500.0 µM (HQ, RC). The NSGO/GCE sensor exhibited excellent reproducibility and stability, with its practical utility validated through real water sample testing. In supercapacitor applications, the NSGO electrode achieved an impressive gravimetric capacitance of 373 F g-1 in 1 M H2SO4 solution at 0.5 A g-1. Symmetric supercapacitor analyses demonstrated that the NSGO cell in 0.01 M KI-0.01 HQ/1 M H2SO4 achieved an enhanced energy density of 65 Wh Kg-1 at 4 A g-1, which is three times superior to 0.01 M HQ/1 M H2SO4 (21.7 Wh Kg-1).