Graphene Oxide Modified Pencil Graphite Electrode for the Detection of H2O2

Abstract

In this work, we propose a new, robust and reliable way to detect H2O2. Reduced graphene oxide-supported tin oxide (SnO2-rGO) as electrochemical sensing material has been synthesized and drop cased on pencil graphite electrode (PGE) for the detection of H2O2. Electrochemical characterization has been done using cyclic voltammetry (CV) and amperometry. Hydrothermal synthesis method was used for the fabrication of SnO2 nanoparticles and GO prepared by modified Hummers method. For the detection of H2O2, the nanoparticles were mixed with Nafion and chitosan before drop coating onto the PGE surface. In this work, we have found a good catalytic activity of SnO2-rGO modified 3B PGE at pH 7.4. Electrochemical studies showed that the sensing platform fabricated using SnO2-rGO possesses fast mass transport, good electrical conductivity and high sensitivity and selectivity for the detection of H2O2. SnO2- GO/PGE exhibited amperometric sensitivity of 53.4 μAmM−1cm-2 with a response time 2s, limit of detection of 0.09μM (n=3), and linearity range of 1-7 mM. The electrode can be prepared simply and at low cost, and present a promising tool for sensing H2O2.