【作者】 易建龙；

【导师】 曾跃；

【作者基本信息】 湖南师范大学 ， 应用化学， 2005， 硕士

【摘要】 染料修饰电极因其在电催化、电分析等方面有许多应用的诱人前景,而受到广泛重视。因此对于染料修饰电极的电聚合机理研究是非常有意义的。 本文用现场紫外可见光谱电化学、红外光谱、电化学石英晶体微天平以及热电化学等方法研究了中性红的电聚合机理。实验表明,聚合前的电引发有利于获得更好的聚合物膜。电引发的作用是产生阳离子自由基,该阳离子自由基与中性红单体或另外一个阳离子自由基反应生成中性红低聚合物,中性红低聚合物能在更低的电位下氧化成相应的阳离子自由基,并进一步与中性红单体或另外一个阳离子自由基反应生成更大分子量的中性红聚合物。因此聚合前的电引发有利于中性红在较低的电位区间的电聚合并获得好的聚中性红膜。 用现场紫外可见光谱电化学和电化学石英晶体微天平研究了核黄素修饰电极的电化学行为。现场紫外可见光谱表明,不同的pH下聚核黄素的存在形态不同,其电聚合机理随着pH变化而有明显变化。 应用循环伏安等方法研究了聚中性红和聚核黄素修饰电极对H₂O₂,KI等氧化过程的电催化特性。聚中性红对H₂O₂的氧化有非常显著的电催化活性;而核黄素修饰电极对KI的氧化有强烈的电催化作用,并初步探讨了上述电催化反应机理。更多还原

【Abstract】 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.更多还原