【作者】 甄晓燕；

【导师】 武克忠；

【作者基本信息】 河北师范大学 ， 物理化学， 2011， 硕士

【摘要】 化学修饰电极是当前电化学、电分析化学方面十分活跃的研究领域。目前已应用于生命科学、环境科学、分析科学、材料科学等方面。导电聚合物聚苯胺修饰电极具有多孔、均相、良好的导电性、合成简单、环境稳定性等优势,但是聚苯胺修饰电极的导电性性能和催化性能较差。为了优化聚苯胺修饰电极的性能,本论文利用电化学循环伏安法在盐酸体系中合成了不同过渡金属离子(M²⁺=Ni²⁺,Mn²⁺,Co²⁺,Zn²⁺,Cu²⁺)掺杂聚苯胺修饰电极,对其电化学行为及结构,形貌对比分析;探讨了氯化铜掺杂引起聚苯胺的特殊增益效应的本质原因;利用特殊增益效应原理,研究了聚苯胺传感器对铜离子浓度的检测。主要内容如下:（1）利用循环伏安法合成五种不同过渡金属离子(M²⁺=Cu²⁺, Mn²⁺, Co²⁺, Ni²⁺, Zn²⁺)掺杂的聚苯胺修饰电极。对其进行红外光谱,扫描电镜及电化学阻抗的研究。结果表明,铜离子掺杂的聚苯胺与其它几种过渡金属离子相比,存在较大差异:其峰型由三对可逆氧化还原峰变成了两对明显的氧化还原峰,且第一对氧化还原峰峰电流明显远远大于其他金属离子的掺杂,出现电流的增益现象。（2）通过设计三组实验改变体系中的阴离子种类探究铜离子掺杂聚苯胺增益现象的本质,结果表明只有在酸性溶液中铜离子和氯离子共存才能导致聚苯胺的增益效应。根据配位理论,论证了五种过渡金属离子与聚苯胺主链配位结构的不同引起了苯胺聚合速度不同及聚苯胺电活性的差异。（3）利用循环伏安法制备了聚苯胺修饰电极,对聚苯胺修饰电极进行XRD,SEM,TG等表征。研究了铜离子在该修饰电极上的电化学行为。实验表明:聚苯胺修饰电极对铜离子有良好的电化学响应,线性范围1×10^-61×10^-3mol/L,最低检测限为2.1369×10^-6mol/L。可以作为检测水中铜离子浓度的一种新方法。更多还原

【Abstract】 The chemically-modified electrodes（CME） have been a most burgueoning and of the most flourish research realms in the electrochemistry and electroanalytic chemistry. It was for the moment widely appied in many case such as life sicence, envioronment sicence, energy source sicence, analytic sicence, electronics and meterial sicence. The polyaniline modified electrode has multihole, homogeneous, good electrical conductivity, environmental stability and other advantages. However, the conductivity performance and catalytic performance of polyaniline modified electrodes is poor. In order to optimize the performance of polyaniline modified electrode, in ous papers we study the effect of transition metal ions (M²⁺=Cu²⁺, Mn²⁺, Co²⁺, Ni²⁺, Zn²⁺) on the electrochemical synthesis of polyaniline was carried out under cyclovoltammetric conditions with the corresponding metal chloride in hydrochloric acid electrolyte. The products were characterized by FT-IR spectroscopy, SEM and EIS. we also reseach the reason of the current plus of the polyaniline doped by copper ion, and electrochemically synthesised polyaniline/Pt （PANI） can be used to measure copper ion concertraions. The main contents are as follows:（1）Polyaniline containing transition metal ions(M²⁺=Cu²⁺, Mn²⁺, Co²⁺, Ni²⁺, Zn²⁺) were synthesized by cyclic voltammetric with the corresponding metal chloride in solution. The products were characterized by FT-IR spectroscopy, SEM and EIS. Experimental results shows that the film of Pani-Cu²⁺ is obviously different to Pani-M²⁺(M²⁺= Ni²⁺, Mn²⁺, Co²⁺, Zn²⁺) in both the shape of oxidation-reduction peaks and the first anodic peak current. Moreover, a particular phenomenon, i.e., a current plus was observed on the I-E curve of Pani-Cu2+ for the first oxidation peak.（2）To discover the reason of the current plus of Pani-Cu²⁺, the experiment was carried for three groups in different electrolytical solutions by cyclic voltammogram. The experimental results shows that the co-activation of copper ion and chloride ion in acid solution accelerates the polymerization rate of aniline, which lead to that the first anodic peak current of Pani-Cu²⁺ increases sharply. According to the coordination theory, the different polymerization rate is caused by the different structure of transition metal ions at the same electrolytical concentration. Transition metal ions are able to coordinate to imine nitrogen atoms of the polymer backbone. The structures of compositions MCl₄^2- made up of corner-sharing MCl₆ octahedra or planes of isolated MCl4 tetrahedra in HCl solutions.（3）A new chemically modified Pt electrode under cyclovoltammetric conditions has been prepared by using polyaniline as a modifier, the electrochemical behavious of copper（Ⅱ） ion on the modified electrode have been studied. The polyaniline electrode was studied by X-ray diffraction, Scanning Electron Microscope and TG analysis. A new approach is developed for sensitive and accurate determintion of copper ion by the polyaniline electrode, the peak of copper ion on polyaniline/Pt is proportional to concentration of copper ion between 1×10^-61×10^-3mol/L,the detection limit is 2.1369×10^-6mol/L.更多还原