多肽对一维Pt纳米结构的控制合成及其电催化应用

发布时间：2018-01-14 23:00

本文关键词：多肽对一维Pt纳米结构的控制合成及其电催化应用　出处：《中国石油大学(华东)》2015年硕士论文　论文类型：学位论文

【摘要】：由于具有较高的催化活性和较好的导电性能,一维Pt纳米结构的制备和组装成为燃料电池领域的研究热点。在制备一维Pt纳米结构的方法中,模板法作为一种有效的合成方法越来越受到人们的重视。由于组成多样、序列可调、合成简单、含多种活性基团、环境友好以及独特的自组装和特异性吸附性能,多肽被用于一维Pt纳米结构的研究中。本课题主要采用多肽模板诱导合成一维Pt纳米结构,考察多肽浓度、多肽模板与Pt前驱体离子相互作用对一维Pt纳米结构的影响,并探索调控剂多肽P7A、BP7A、S7、T7对多肽模板诱导的一维Pt纳米结构的结构与形貌调控,并研究其作为电催化剂在电化学中的应用。利用I_3K模板原位还原法,通过改变肽模板与Pt前驱体的浓度比,在温和条件下制备随着肽模板与Pt前驱体浓度比改变而直径改变的一维连续Pt纳米纤维结构,在二者浓度比为1:10条件下,一维Pt纳米纤维直径最大。考察其电催化性能发现:二者在浓度比为1:10时,其单位质量的有效活化面积(specific Electrochemical Activity Surface Area,specific ECSA)最大,并高于商业化Pt/C催化剂;对甲醇阳极氧化反应显示各浓度比下的一维Pt纳米纤维都具有高于商业化Pt/C催化剂的If/Ib,表明其具有更高的抗CO等含碳中间产物中毒能力;另外,为了考察其作为电催化剂的使用寿命,对一维Pt纳米纤维和商业化Pt/C催化剂进行加速耐久性实验,结果表明,在1000个循环伏安(Cyclic Voltammetry,CV)曲线后,一维Pt纳米纤维失活率低于商业化Pt/C催化剂,因而具有更高的稳定性。在1:10的肽模板与Pt前驱体浓度比下,分别采用I_4K_2、I_3CGK、I_3H为模板,在温和条件下制备一维Pt纳米纤维结构。借助透射电子显微镜(TEM)观察发现,I_4K_2诱导下形成一维连续的Pt纳米纤维,而I_3CGK、I_3H诱导下形成Pt纳米颗粒有序排列的一维纳米结构。考察其电催化性能发现:I_4K_2诱导的一维连续的Pt纳米纤维具有高于商业化Pt/C催化剂的单位质量的ECSA、抗中毒能力和稳定性;尽管I_3CGK、I_3H诱导形成的一维Pt纳米结构催化活性低于商业化Pt/C催化剂,但对甲醇阳极氧化表明其具有更高的抗中毒能力和催化稳定性。在I_3K诱导的一维Pt纳米纤维体系中进一步引入调控剂P7A、BP7A、S7、T7,实现微观形貌特征的结构调控。借助TEM观察发现:(1)加入少量P7A调控剂,形成连续性较差的一维Pt纳米结构,而提高P7A的加入量后,得到由完全分散的Pt纳米颗粒有序组装的一维Pt结构;(2)加入少量BP7A调控剂,得到表面光滑、连续排列的一维Pt纳米结构,在提高其加入量后,一维Pt纳米结构连续性变差;(3)加入能特异性吸附Pt(111)面和Pt(100)面的S7和T7,分别得到连续性较差和连续性较好的一维Pt纳米结构。尽管加入调控剂后,一维Pt纳米结构的催化活性降低,但是仍具有较高的抗中毒能力。
[Abstract]:Because of the high catalytic activity and good conductive properties of 1D Pt nanostructures were prepared and assembled into a research hotspot in the field of fuel cell. The preparation methods of one-dimensional Pt nanostructures, template synthesis method is effective as more and more attention. Because of diversity, the sequence is adjustable. Simple synthesis, containing a variety of active groups, environmental friendly and self-assembly and specific adsorption properties of the unique polypeptide was used in the study of one-dimensional Pt nanostructures. The main topic of the use of peptide template induced synthesis of one-dimensional Pt nanostructures, effects of polypeptide concentration and Pt template, polypeptide precursor ion interaction of one-dimensional Pt nanostructures, and explore the regulatory agent polypeptide P7A, BP7A, S7, control the structure and morphology of one-dimensional Pt nanostructures on T7 peptide induced by the template, and study its as a catalyst in the electrochemical application By using I_3K reduction method. In situ template, by changing the concentration of peptide template and Pt precursor, preparation of peptide as template and Pt precursor concentration and diameter change change than one-dimensional continuous Pt nano fiber structure under mild conditions, the two concentration ratio is 1:10, the maximum diameter of one dimensional Pt nano fiber the electrocatalytic performance. The research found that: two the concentration ratio was 1:10, the quality of the effective activation area unit (specific Electrochemical Activity Surface Area, specific ECSA), and higher than that of commercial Pt/C catalyst for methanol oxidation reaction; the anode showed that the concentration is higher than that of commercial Pt/C catalyst If/Ib than one-dimensional Pt the nano fibers, indicating that it has a high resistance to CO carbon containing intermediates poisoning; in addition, in order to study the electrical as the service life of the catalyst, catalytic of one-dimensional Pt nano fiber and commercial Pt/C Agent of accelerated durability experiment, results show that in the 1000 cyclic voltammetry (Cyclic Voltammetry CV) curve, the one-dimensional Pt nano fiber inactivation rate is lower than the commercial Pt/C catalyst, so it has higher stability. In the template and Pt peptide precursor concentration ratio 1:10, respectively by I_4K_2 and I_3CGK. I_3H as a template, the preparation of one-dimensional Pt nano fiber structure under mild conditions. By means of transmission electron microscopy (TEM) observation showed that I_4K_2 induced formation of one-dimensional continuous Pt nanofibers, and I_3CGK, I_3H induced formation of one-dimensional nano structure of Pt nano particle ordered. The electrocatalytic properties found: one-dimensional induced by I_4K_2 the continuous Pt fiber has the unit quality is higher than the commercial Pt/C catalyst ECSA, anti poisoning ability and stability; while I_3CGK, the catalytic activity of I_3H one-dimensional Pt nanostructures induced the formation of lower than that of commercial Pt/C catalyst Agent, but it has better anti poisoning ability and stability of catalytic methanol oxidation. In that one-dimensional Pt nano fiber system induced by I_3K in the further introduction of control agent P7A, BP7A, S7, T7, the structure of regulation morphology. With the aid of the TEM observation: (1) adding a small amount of P7A regulator and the formation of one-dimensional Pt nanostructures is continuous, and increase the amount of P7A, obtained Pt structure by Pt nanoparticles dispersed completely ordered assembly; (2) adding a small amount of BP7A regulating agent, surface smooth, continuous arrangement of one-dimensional Pt nano structure, improve its quantity, dimension Pt nano structure of continuous variation; (3) adding specific adsorption of Pt (111) and Pt (100) S7 and T7 surface, poor continuity and good continuity of one-dimensional Pt nanostructures were obtained. Despite the added control agent, reduce the catalytic activity of Pt nanowires, but It still has a high ability to resist poisoning.

【学位授予单位】：中国石油大学(华东)
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：O643.36;TB383.1

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