Facile preparation of MnO2 nanotubes/reduced graphene oxide nanocomposite for electrochemical sensing of hydrogen peroxide

We report the synthesis and application of MnO2 nanotubes/reduced graphene oxide nanocomposite (MnO2 NTs/RGO NCs) for the detection of hydrogen peroxide. The MnO2 NTs/RGO NCs were synthesized via a simple single-step hydrothermal process in acidic KMnO4 solution without the use of surfactants or templates. The nanocomposites were synthesized with different percentages of RGO (1, 3 and 5%). Field emission scanning electron microscopy, transmission electron microscopy and X-ray diffraction results confirmed the growth of MnO2 NTs on the RGO surface. Electrochemical properties of the MnO2 NTs/RGO NCs electrode were investigated by amperometry, cyclic voltammetry and electrochemical impedance spectroscopy. The observations confirmed that the charge transfer resistance of the glassy carbon electrode (GCE) coated with MnO2 NTs/RGO NCs was significantly decreased. The limit of detection and limit of quantification (S/N = 3) of two linear segments (0.1-30 mM and 40-80 mM of H2O2) are estimated as 1.29 μM, 4.29 μM and 0.82 μM, 2.75 μM, respectively. The reproducibility experiment results prove that the use of MnO2 NTs/RGO NCs is feasible for the quantitative detection of H2O2 in the range of 0.1-80 mmol L−1.