【作者】 臧杨；

【导师】 郝晓刚；

【作者基本信息】 太原理工大学 ， 化学工程， 2010， 硕士

【摘要】 有机-无机纳米复合材料能够兼具有机材料和无机材料的优异性能,产生协同优化效应甚至新的功能,在材料科学与器件制造领域日益受到人们的关注。在众多有机-无机复合材料中,聚苯胺(PANI)与铁氰化镍(NiHCF)的复合有利于提高材料的整体性能,在超级电容器(ESC)、电催化与生物传感器等方面有广泛的研究前景。我们的工作主要包括下面两个方面的内容:首先,我们采用循环伏安一步共聚法在碳纳米管修饰的铂基体上制备了电活性碳纳米管/聚苯胺/铁氰化镍(CNTs/PANI/NiHCF)复合膜。用傅立叶变换红外光谱(FT-IR)、X射线能谱仪(EDS)和扫描电镜(SEM)研究了复合膜组成及其表面形貌,并用循环伏安(CV)、恒电流充放电和电化学阻抗(EIS)等测试了复合膜的循环稳定性与电化学容量性能。研究表明:复合膜为三维多孔有序的网络状结构,PANI和NiHCF以纳米颗粒形式存在并沿CNTs均匀分布;在电流密度为2 mA/cm2时,CNTs/PANI/NiHCF复合膜的比容量高达262.28 F/g,比能量为29.51 Wh/kg,电流密度为10 mA/cm2时比功率可达10228.61 W/kg;在2000次循环充放电过程中,复合膜的电容量仅衰减19.92%,电荷充放电效率一直保持在99%以上。再次,通过调节制备液中苯胺单体浓度对其粒径进行有效控制,合成了三种不同尺寸的PANI-NiHCF纳米复合颗粒。初步探讨纳米颗粒的形成机理并研究其组成/结构-性能的关系;通过X射线能谱仪、扫描电镜与傅立叶变换红外光谱研究纳米颗粒的组成及其微观结构;用循环伏安、电化学阻抗等技术测试纳米颗粒的电荷传递动力学与电化学性能。实验表明:PANI-NiHCF纳米颗粒均呈立方体结构,分散性较好;PANI-NiHCF-I具有较好的电荷传递动力学特征,其电荷传递系数α为0.467;经1000次循环之后,PANI-NiHCF-II的离子交换容量仅衰减8.7%,具有优异的电化学稳定性;与PANI-NiHCF-III不同,PANI-NiHCF-I与PANI-NiHCF-II均可利用电控离子交换技术(ESIX)对碱金属离子进行分析与检测。更多还原

【Abstract】 Organic-inorganic nanocomposite materials can show synergistic effects that suppress undesirable properties of individual components and generate enhanced, even create totally new, functionalities. They have attracted more and more attention because of excellent properties in materials synthesis and device fabrication. Among the vast number of hybrid materials, the combination of polyaniline (PANI) and nickel hexacyanoferrate (NiHCF) has been extensively investigated to improve overall performances of electrochemical supercapacitor (ESC), elec-trocatalysts biosensors and so on. The main contents of our work are summarized as follows:Firstly, the electroactive composite films of CNTs/PANI/NiHCF were synthesized on platinum substrates modified with CNTs by one-step co-polymerization of cyclic voltammetry. The components and morphology of the composite films were characterized by fourier transform infrared spectroscopy (FT-IR), energy dispersive X-ray spectroscopy (EDS), and scanning electron microscope (SEM). Cyclic voltammetry (CV), galvanostatic charge/discharge, and electrochemical impedance spectroscope (EIS) were used to study the cycling stability and electrochemical capacitive performance of the CNTs/PANI/NiHCF film. Experimental results show the three-dimensional porous network composite films with uniform distribution of both PANI and NiHCF nanoparticles along the CNTs are formed by this new method. The specific capacitance of the inorganic-organic hybrid films can reach 262.28 F/g with a specific energy of 29.51 Wh/kg at the current density of 2 mA/cm2, and the specific power is 10228.61 W/kg at the current density of 10 mA/cm2. Meanwhile, the films show that the capacity decay is only 19.92% after 2000 charge/discharge cycles and the coulombic efficiency is over 99%.Secondly, PANI-NiHCF nanocomposite particles with three different size had been achieved by adjusting the concentration of aniline in the process of preparation. The formation mechanism of PANI-NiHCF was discussed and the composition/structure-function relationship was also studied in our Work. The composition and microstructure of nanocomposite particles were analyzed by fourier transform infrared spectroscopy, energy dispersive X-ray spectroscopy, and scanning electron microscope. Cyclic voltammetry and electrochemical impedance spectroscope were used to investigate the dynamics of charge transport and its electrochemical performances. Experimental results show that PANI-NiHCF nanoparticles reveal cube-structure, and are uniform and dispersed. And PANI-NiHCF-I are characterized by high dynamics of charge transport, and the calculated value of the transfer coefficientαis 0.467. PANI-NiHCF-II has good stability, and its capacity decay is only 8.7% after 1000 cycles of potential scan. Compare with PANI-NiHCF-III, PANI-NiHCF-I and II are both detected and analyzed alkali metal cations by electrochemically controlled ion separation.更多还原