Synthesis and characterization of non-enzymatic hydrogen peroxide sensor of polypyrrole coated cobalt nanocomposites

Polypyrrole coated cobalt nanocomposites (PPy-Co NCs) are synthesized and used for the fabrication of the non-enzymatic hydrogen peroxide (H2O2) sensor. The morphology and composition of the nanocomposites are characterized by the Field Emission Scanning Electron Microscope, Fourier Transform Infrared Spectrum, X-ray Powder Diffraction and Thermogravimetric Analysis. The electrochemical response to H2O2 on the PPy-Co NCs/GCE is examined using both cyclic voltammetry and amperometry. Electrochemical investigation indicated that the nanocomposites possess an excellent performance towards H2O2. The modified sensor could detect H2O2 in a linear range of 20 mu M to 80 mM. There are two linear segments (low and high concentration of H2O2). The first linear segment ranges from 20 mu M to 1 mM with a correlation coefficient of 0.99 and the sensitivity of 103.48 mu AmM-1 cm(-2) and the second linear segment ranges up to 80 mM with a correlation coefficient of 0.9905 and the sensitivity of 10.80 mu AmM-1 cm(-2). The detection limit of both ranges is 2.05 and 19.64 mu M respectively at a signal-to-noise ratio of 3. (C) 2014 Elsevier B.V. All rights reserved.