负载贵金属的纳米纤维催化剂的制备及应用研究

发布时间：2018-05-27 21:42

本文选题：静电纺丝 + 贵金属负载　；参考：《吉林大学》2015年硕士论文

【摘要】：近些年来，生物传感器越来越受到人们的关注，这其中对神经递质类物质的检测研究尤为热门，而利用电化学方法检测，是现在最常用的方法之一。电化学传感器发展迅猛，不仅成本低廉、响应迅速，而且结果准确，是目前最好也是最方便的检测方法，越来越成为电化学领域研究的热点，这其中找到合适的修饰物来修饰电极以提高测试的准确性和灵敏度就是关键。另外，除了对已有物质的检测以外，目前人类社会正面临严重的环境污染和能源危机，所以寻找新的对人类有益的物质也迫在眉睫。现在科学家们已经开始不遗余力的开发新的清洁能源。氢能源作为最有潜力的新能源之一，已经成了科学家们青睐的研究对象，但目前，氢气的制备和储存仍然面临着很多难以攻克的难题，即使现在已经有能够实际应用的储氢物质存在，但释放其中的氢气也需要苛刻的条件，所以研发能在温和条件下就能让氢气释放的催化剂具有重要的现实意义。静电纺丝因其装置简单、成本低廉、发展较为成熟，已经成为制备一维纳米纤维最有效的办法。一维纳米纤维在用于电极修饰时可以增加电子的流动性，提高电化学传感器的灵敏度，改善电化学传感器的检测能力；加之纳米纤维具有大的比表面积，高的长径比和孔隙率，在用作催化剂基底时能够有效的增加催化位点，，提高催化效率，而且在多相催化反应中，纳米纤维膜的成膜性还为催化剂的回收再利用提供了便捷。综上，本论文基于静电纺丝技术分别制备了金属/无机物和金属/有机物复合纳米纤维，并将其应用于多巴胺的电化学检测和硼烷氨水解制氢的催化中，具体研究成果如下：（1）利用静电纺丝和焙烧相结合的技术，成功制备了CeO2/Au复合纳米纤维。由于Au具有良好的导电性、电化学稳定性和生物相容性，纳米化的CeO2电子晶界电阻小，电导率高，而且无毒、稳定，我们将其复合作为电极修饰物用作多巴胺的电化学检测，得到的检测限（S/N=3）低达0.056M，经过I-t曲线计算得到灵敏度为127A·mM1·cm2，同时在不同扫速的CV曲线中可以看出，整个过程是受到表面扩散速度控制的。该方法为制备多巴胺电化学传感器提供了新的途径。（2）利用静电纺丝和微波还原相结合的技术，成功制备了PAN/Ag/Pd复合纳米纤维，并将其用于催化硼烷氨水解制氢的反应中，经测试得到的催化转化率值（TOF）达到了377.2mol H2·h-1·(mol Pd)-1。又经过四次同样的过程循环测试，仍保持较高催化活性。这是我们首次将金属/聚合物复合纳米纤维催化剂应用在硼烷氨水解制氢的反应中，为硼烷氨水解制氢反应催化剂的制备提供了新的思路。
[Abstract]:In recent years, more and more attention has been paid to biosensors, in which the detection of neurotransmitters is particularly popular. Electrochemical detection is one of the most commonly used methods. Electrochemical sensors are developing rapidly, not only low cost, rapid response, but also accurate results. It is the best and most convenient detection method at present, and has become a hot spot in the field of electrochemistry. The key is to find the right modifier to modify the electrode to improve the accuracy and sensitivity of the test. In addition, in addition to the detection of existing substances, human society is facing serious environmental pollution and energy crisis at present, so it is urgent to find new substances that are beneficial to human beings. Now scientists are sparing no effort to develop new clean energy sources. Hydrogen energy, as one of the most potential new energy sources, has become a favorite research object of scientists, but at present, the preparation and storage of hydrogen still face many difficult problems. Even though there are some hydrogen storage materials which can be used in practice, the release of hydrogen also requires harsh conditions. Therefore, it is of great practical significance to develop a catalyst that can release hydrogen under mild conditions. Electrostatic spinning has become the most effective method for the preparation of one-dimensional nanofibers because of its simple device, low cost and mature development. One-dimensional nanofibers can increase the mobility of electrons, improve the sensitivity of electrochemical sensors and improve the detection ability of electrochemical sensors when they are used for electrode modification. In addition, nanofibers have large specific surface area, high aspect ratio and porosity. When used as the catalyst substrate, it can effectively increase the catalytic sites and improve the catalytic efficiency. In the heterogeneous catalytic reaction, the film-forming property of the nanofiber membrane also provides a convenient way for the recovery and reuse of the catalyst. In this thesis, metal / inorganic and metal / organic composite nanofibers were prepared based on electrospinning technology, and were applied to the electrochemical detection of dopamine and the catalytic reaction of borane ammonia to produce hydrogen. The results are as follows. 1) CeO2/Au nanofibers were successfully prepared by using the technology of electrostatic spinning and roasting. Due to the good conductivity, electrochemical stability and biocompatibility of au, the nanocrystalline CeO2 has low resistance, high conductivity, nontoxic and stable, so we used it as an electrode modifier for the electrochemical detection of dopamine. The detection limit is as low as 0.056M.The sensitivity is 127A mM1 / cm ~ 2 calculated by I-t curve. It can be seen that the whole process is controlled by the surface diffusion velocity in the CV curves of different sweep speeds. This method provides a new way for the preparation of dopamine electrochemical sensor. (2) PAN/Ag/Pd composite nanofibers were successfully prepared by electrospinning and microwave reduction, and were used to catalyze the hydrolysis of borane to hydrogen in aqueous solution. The measured catalytic conversion value of TOF was up to 377.2mol H 2h -1 / mol PdN 1. After four cycles of the same process, the catalytic activity remained high. This is the first time that the metal / polymer nanofiber catalyst has been used in the hydrolysis of borane to produce hydrogen, which provides a new idea for the preparation of catalyst for the hydrolysis of borane to hydrogen.
【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：O643.36;TQ116.2

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