Synthesis of polypyrrole coated manganese nanowires and their application in hydrogen peroxide detection

This study focuses on the synthesis and application of polypyrrole coated manganese nanowires (Mn/PPy NWs) as an enzyme-less sensor for the detection of hydrogen peroxide (H2O2). The X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) results confirm a core–shell structure with the Mn nanowires encapsulated by the PPy. An electrochemical sensor based on the Mn/PPy NWs for amperometric determination of H2O2 is prepared. The electrochemical behaviour of H2O2 is investigated by cyclic voltammetry with the use of modified glassy carbon electrode (GCE) with Mn/PPy NWs film. The modified glassy carbon electrode (GCE) with Mn/PPy NWs shows enhanced amperometric response for the detection of H2O2. This is due to the high available surface area of Mn/PPy NWs which can provide a suitable area for the reaction of H2O2. The detection limit and limit of quantification (S/N = 3) for two linear segments (low and high concentration of H2O2) are estimated to be 2.12 μmol L−1, 7.07 μmol L−1 and 22.3 μmol L−1, 74.5 μmol L−1, respectively. In addition, the sensitivity for these two linear segments is 0.4762 μA mM−1 and 0.0452 μA mM−1 respectively. - Graphical abstract: Display Omitted - Highlights: • Polypyrrole coated Manganese nanowires (Mn/PPy NWs) were prepared. • The Mn/PPy NWs provided a high available surface area to react with H2O2. • The calibration curve showed two linear segments of H2O2 concentration. • The sensitivity of the low concentration was 0.4762 μA mM−1. • The LOD of low and high concentration was 2.12 μM and 22.3 μM respectively