Electropolymerization And Electrocatalytic Characters Of Poly Neutral Red And Poly Flavins Modified Electrodes

Dyes modified electrodes have attracted much attention due to their promising electrocatalytic and analytical applications. It is very necessary to investigate their mechanisms of electropolymerization.In this thesis, the electropolymerization of neutral red (NR) has been studied by means of in situ UV-vis spectroscopy, Fourier Transform Infrared Reflection Spectroscopy (FTIR), Electrochemical Quartz Crystal Microbalance (EQCM) and in situ thermoelectrochemistry measurements to obtain the information about the electropolymerization mechanism of neutral red. The experimental results showed that during the electro-initiation process a radical-cation was produced by means of electrooxidation at a high potential and reacted further with other radicals or monomers to form the oligomer that can be more easily oxidated to a radical-cation at a lower potential. Consequently by the electro-initiation the electropolymerization of neutral red can be accomplished on a narrow potential range and the excellent poly neutral red films can be obtained.The electrochemistry behavior of poly-flavins modified electrode was investigated by means of in situ UV-vis spectroscopy and EQCM. The results of in situ UV-vis spectroscopy showed that they are different types at various pH. Electropolymerization mechanism of flavins is dependent on pH.The electrocatalytic oxidation of H₂O₂ and KI etc on Poly-neutral red and polyflavins modified electrodes were investigated by means of cyclic voltammetric measurements. Poly-neutral red and Poly-flavins have strong electrocatalytic activities on the oxidation of H₂O₂ and KI, respectively. Their electrocatalytic mechanisms were discussed also.