Novel polypyrrole-graphene oxide-gold nanocomposite for high performance hydrogen peroxide sensing application

Abstract

Hydrogen peroxide (H2O2) plays a major role in the signaling processes in various diseases and its qualitative or quantitative analyses are of paramount importance in healthcare, process, and food, etc. In this study, an electrochemical ultra-high sensor has been reported for the detection of H2O2 based on nanocomposites consisting of polypyrrole (PPy), graphene oxide (GO), and gold nanoparticles (AuNPs). These nanocomposites were studied using scanning electron microscopy, ultraviolet-visible, Fourier transform infrared, Raman spectroscopies and cyclic voltammetry techniques. The obtained final electrode (PPy-GO-AuNPs/GCE) showed high electrocatalytic activity towards H2O2 allowing the detection of H2O2 at a negative potential at the range of -20 V vs.Ag/AgCl. The amperometric response of the non-enzymatic H2O2 sensor exhibited a higher sensitivity of 41.35 μA/mM at linear range around 2.5−25 mM, and a low detection limit of 5 μM (S/N = 3). The practical applicability of nanocomposites was also investigated for H2O2 sensing in real milk. These results suggest that PPy-GO-AuNPs/GCE nanocomposite is promising and effective for low concentration detection with higher sensitivity and wider linear response range as compared to the previously reported H2O2 sensors. Furthermore, these nanocomposites show higher stability, repeatability and reproducibility of the sensing data indicating their potential as long term practical applications. © 2021 Elsevier B.V.