【作者】 张金花；

【导师】 褚道葆；

【作者基本信息】 安徽师范大学 ， 有机化学， 2005， 硕士

【摘要】 论文主要内容分以下三个部分: 第一部分纳米TiO₂膜电极的交流阻抗谱及控电位暂态电化学研究用电化学阻抗谱（EIS）、循环伏安法和循环方波伏安法研究了纳米TiO₂ 膜电极在两种不同溶液中的电化学行为,给出了相应的等效电路和动力学参数。结果表明,纳米TiO₂ 膜中存在TiO₂/Ti₂O₃ 和TiO₂/Ti（OH）₃ 两对氧化还原可逆电极过程; 外加电位和电解液的性质对纳米TiO₂ 膜的界面结构和表面电化学反应速度有显著影响, 在膜反应电位区间电极阻抗主要由膜电阻Rf﹑电化学极化电阻Rct 和Warburg 阻抗Zw 组成,在1 mol/ L H₂SO₄ 溶液和含有乙醇的0.5 mol/L HAc-NaAc 缓冲溶液中的Rf 分别为125Ω·cm² 和7.45×10³Ω·cm², 同时由于纳米TiO₂膜表面粗糙度和不均一性的影响, 存在弥散效应。第二部分纳米TiO₂/碳纳米管（nano-TiO₂/CNT）复合膜修饰电极的电化学性能研究采用电合成前驱体直接水解法制备nano-TiO₂ 膜修饰电极,利用掺杂碳纳米管对纳米TiO₂膜进行改性, 通过交流阻抗谱（EIS）、循环伏安、阻抗-电位、计时库仑法以及透射电子显微镜（TEM）等方法,研究了nano-TiO₂/CNT 复合膜修饰电极的电化学性能,由于大量碳纳米管的存在,阻碍了nano-TiO₂成膜时的团聚作用,使nano-TiO₂尽可能地更多还原

【Abstract】 The paper is composed of the following three parts: First, Electrochemical impedance spectra 、cyclic osteryoung square wave voltammogram and cyclic voltammogram of nano-TiO₂ Electrode. The electrochemical behavior of Ti/nano-TiO₂ film electrode was investigated by Electrochemical Impedance Spectra（EIS）、Cyclic Voltammogram（CV）and Cyclic Square Wave Voltammogram（CSWV） in two different solutions, and relevant equivalent circuit and electrochemical kinetic parameters were presented. The results indicate that there are two pairs of well-defined redox peaks for Ti/nano-TiO₂ film in correspondence with TiO₂/Ti₂O₃ and TiO₂/Ti（OH）₃ two heterogeneous redox reversible electrode process; and applied electric potential and the quality of electrolyte have prominent influence on the interface structure and superficial electrochemical reaction speeds, electrode impedance consisted of film resistance Rf、electrochemical polarization impedance Rct and Warburg impedance Zw in the potential range of film reaction, The Rf are 125Ω·cm² and 7.45×10³Ω·cm² respectively in 1 mol/L H₂SO₄ and 0.5mol/L HAc-NaAc buffer electrolyte included ethanol, and there were dispersion effect due to the roughness and inhomogeneity of nano-TiO₂ film surface. Second, Electrochemical performance on nano-TiO₂/CNT composite film modified electrode. In terms of Electrochemical Impedance Spectra（EIS）、Cyclic Voltammetry、Chronocoulometry、Impedance-potential and TEM, We researched and compared the electrochemical characteristic difference between composite nano-TiO₂/C-nanotube （nano-TiO₂/CNT） modified electrode and pure nano-TiO₂ modified electrode, a great deal of carbon nanotubes are in existence, which can block the reunite effect of nano-TiO₂ particle. The unique atomic structure of carbon nanotube can accelerate electron transfer in electrochemical reaction and bring proper catalytical response. Compare to pure nano-TiO₂ modified electrode, the current values of the second redox peaks of nano-TiO₂/CNT modified electrode are about twice higher than pure nano-TiO₂ modified electrode’s, and quantity of electric charge increases greatly at the same time. and it is further proved by the heterogeneous electrocatalytic reduction of maleic acid etc. Third, Studies on amino acid chiral modified electrode. L-Cysteine-nano-TiO₂/CNT（L-Cys-nano-TiO₂/CNT） chiral modified electrode was prepared by self assemble and several methods such as FTIR spectrum, Scanning Electron Microscopy, Impedance,Cyclic Voltammogram were used to investigate the electrochemical properties on the surface,and we electrodeposited Ag on the nano-TiO₂/CNT surface with electrochemical scan, and got L-Cys-Ag–nano-TiO₂/CNT chiral modified electrode by self assemble. There were a pair of redox peaks of Ag-nano-TiO₂/CNT electrode in 1mol/L H₂SO₄, L-Cys-Ag–nano -TiO₂/CNT chiral electrode had proper electrocatalytic activity to hypnone reduction,and it was rather stability.更多还原