Electrochemical detection of nitrite (NO2) with PEDOT:PSS modified gold/PPy-C/carbon nitride nanocomposites by electrochemical approach

This study was performed to prepare gold-modified-PPy(polypyrrole)-C/C3N4 nanocomposites (NCs) by simple pyrolysis and ultra-sonication techniques. The prepared NC was coated onto glassy carbon electrode (GCE) to achieve a modified, active working electrode of nitrite (NO2) electrochemical sensor. The structural morphology, crystallographic study, and opto-electronic properties of NCs were evaluated applying Field-Emission Scanning Electron Microscopy (FESEM), Energy Dispersive Spectroscopy (EDS), High-Resolution Transmission Electron Microscopy (HRTEM), Brunauer-Emmett-Teller (BET), powder X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and Ultraviolet-visible spectroscopy (UV-vis.) analysis. Besides this, the electrochemical characterization of NCs was assessed by cyclic voltammetry (CV) and displayed substantial outcome favorable to electron sensing substrates. The working electrode prepared by coating of Au@PPy-C/C3N4 NCs on GCE using conducting binder poly(3,4-ethylenedioxythiophene) poly-styrene sulfonate (PEDOT:PSS), which exhibited linear electrochemical responses applying differential pulse voltammetry (DPV) to the detection of NO2 in a wider range of 1.5 similar to 22.5 mu M in 7.0 pH buffer defined as linear dynamic range (LDR). Additionally, the NO2 sensor showed good sensitivity (91.1899 mu A mu M(-1)cm(-2)) and low limit of detection (LOD; 1.11 +/- 0.05 mu M) which are appreciable. Other parameters, reproducibility and response time were investigated properly and also found as reliable. Furthermore, the assembled sensor based on Au@PPy-C/g-C3N4 NCs/GCE disclosed its consistent performances in analyzing of environmental samples. Thus, this study exposed a facile strategy to the development of efficient electro-chemical sensor using organometallic nanocomposites. (c) 2023 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.