An amperometric hydrogen peroxide chemical sensor based on graphene-Fe₃O₄ multilayer films modified ITO electrode

In this article, poly(diallydimethylammonium chloride) (PDDA) functionalized graphene-Fe(3)O(4) (PDDA-G/Fe(3)O(4))(n) multilayer films were fabricated with layer-by-layer assembly of negatively charged Fe(3)O(4) nanoparticles (Fe(3)O(4) NPs) and positively charged PDDA-G through the electrostatic interaction to construct a H(2)O(2) chemical sensor. The multilayer films were characterized with UV-vis spectroscopy, atomic force microscopy and cyclic voltammetry. The participation of PDDA-G improved the catalytic ability of Fe(3)O(4) NPs due to its high surface area and excellent electric conductivity. Based on this, the obtained H(2)O(2) chemical sensor exhibited prominent electrocatalytic activity for the detection of H(2)O(2) with a wide linear range from 20 μM to 6.25 mM, a rapid response upon the addition of H(2)O(2) and a low detection limit of 2.5 μM with the signal to noise ratio of three. Furthermore, the fabricated nonenzymatic H(2)O(2) chemical sensor exhibited excellent stability and reproducibility.