Non‐enzymatic Electrochemical Oxidation Based on AuNP/PPy/rGO Nanohybrid Modified Glassy Carbon Electrode as a Sensing Platform for Oxalic Acid

Abstract In this study, a nanohybrid of gold nanoparticle, polypyrrole, and reduced graphene oxide (AuNP/PPy/rGO) was prepared by an in‐situ chemical synthesis approach. The as‐prepared nanohybrid has been applied for non‐enzymatic electrochemical detection of oxalic acid (OA). The nanohybrid nanocomposite material (AuNP/PPy/rGO) was characterized by field emission scanning electron microscopy (FE‐SEM), X‐ray diffraction (XRD), Fourier transform infrared (FT‐IR) spectroscopy and cyclic voltammetry (CV), and further employed as novel sensing material to quantify OA. Compared with PPy/rGO, the AuNP/PPy/rGO nanocomposite showed enhanced electrocatalytic activity towards OA oxidation. The oxidation current of OA is linear to its concentration in the range of 0.05 mM to 7 mM with a lower detection limit of 0.02 mM. The experimental results also showed that the fabricated sensor has good reproducibility (R.S.D=2.59 % for 0.5 mM, n=3), high sensitivity (91 μA/mM), excellent stability and good anti‐interference property against electroactive compounds and metal ions.