Voltammetric and microscopic characteristics of MnO2 and silica-MnO2 hybrid films electrodeposited on the surface of planar electrodes

International audience; The morphological and electrocatalytic properties of ITO and nanostructured carbon screen printed electrodes (nanoSPCE) modified with thin films of MnO2 particles, alone or as hybrid with SiO2, as obtained using electrodeposition techniques, were studied. The time and potential of MnO2 electrodeposition influenced the electrocatalytic properties of the modified electrodes towards H2O2. The highest electrocatalytic current was observed at deposition potential E=-0.8 V and deposition time of 10 s. MnO2 particles with uniform distribution were obtained onto the electrode surface when prepared under optimal conditions. The nanoSPCE-MnO2 has demonstrated larger effective surface area and faster charge transfer rates compared to ITO-MnO2. The electrodeposited silica, in addition to MnO2, improved the operational stability of the electrodes without noticeable decreasing of their performance. Modified electrodes were used for hydrogen peroxide determination.