Green and large-scale one-pot synthesis of small-sized graphene-bridged manganese dioxide nanowire network as new electrode material for electrochemical sensing

Abstract

The cross-linked MnO2 nanowire (MNWS) network bridged with small-sized graphene (SSGS) with a uniform size of ~200 nm is prepared by a one-pot green hydrothermal route from graphene oxide sol and KMnO4. The route causes KMnO4 to react and form MnOx through both self-decomposition and etching graphene, as a result that MnOx grow into nanowires and micrometer-scale graphene is cut into SSGS simultaneously. The as-prepared MNWS/SSGS is characterized by scanning electron microscope, transmission electron microscope and X-ray diffractometer. The electrocatalytic activity of MNWS/SSGS for H2O2 reduction is studied by means of cyclic voltammetry and chronoamperometry. The MNWS/SSGS modified glassy carbon electrode exhibits a sensitive and prompt amperometric response to H2O2, with a sensitivity of 56 μA mM−1 and detection limit as low as 0.54 μM. These outstanding performances demonstrate that MNWS/SSGS is promising for fabrication of electrochemical sensors. Importantly, this study may offer a novel and insightful approach for the preparation and development of advanced materials based on the bridging architecture.