Photo-reduction assisted synthesis of MnO2/reduced graphene oxide/P25 for electrochemical detection of hydrogen peroxide

Abstract

In this work, we report the synthesis of MnO₂/RGO (reduced graphene oxide)/P25 nanocomposites for a non-enzymatic hydrogen peroxide sensor. MnO₂/RGO/P25 nanocomposites were synthesized with a photo-reduction approach and characterized by field emission scanning electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and Raman spectroscopy. A non-enzymatic hydrogen peroxide sensor was fabricated by dropping MnO₂/RGO/P25 nanocomposites on the surface of a glassy carbon electrode. Electrochemical measurements of the MnO₂/RGO/P25 modified electrode were carried out on an electrochemical workstation. The as-prepared sensor exhibited high electrocatalytic activity, selectivity and stability towards the oxidation of H₂O₂. Under optimum conditions, the calibration curve for H₂O₂ determination was linear in the range from 1.0 × 10⁻⁶ to 4.0 × 10⁻³ M (R² = 0.999) with a detection limit of 3 × 10⁻⁷ M (S/N = 3).