Pt基纳米材料的合成及其对甲醇电催化的研究

发布时间：2018-04-05 11:58

本文选题：Pt-M　切入点：纳米　出处：《苏州大学》2015年硕士论文

【摘要】：直接甲醇燃料电池(DMFC)是质子交换膜燃料电池的一种,它具有能量转换效率高、结构简单、环境友好等优点,被认为是最理想的可移动能源之一。目前为止,Pt和Pt基纳米材料仍是最常用作直接甲醇燃料电池的阳极材料,但是由于Pt的成本太高,自然界储存量较少,这使得直接甲醇燃料电池的商业化受到严重的阻碍。因此,研究一种新型的催化剂,既能降低贵金属Pt的用量又能增强催化剂催化活性和稳定性是迫切需要的。本文主要研究通过形貌控制合成均一的树枝状Pt、Pt-Au纳米催化剂以及凹形树突状Pt Cu合金催化剂对甲醇的电催化氧化性能。具体研究内容如下:(1)通过H2还原法成功合成具有均一结构的Pt纳米枝状材料(Pt NDs),并用溶剂热法成功在已合成的Pt NDs上接Au。用透射电子显微镜(TEM)、X射线衍射(XRD)和能谱(EDX)等方法对其进行物理表征。用电化学方法测试它们对甲醇的氧化还原反应的催化性能。结果表明,Pt NDs和Pt-Au NHs具有较高的电化学活性比表面积(ECSA)和良好的甲醇氧化电化学性能。(2)通过水热法成功合成凹形树突状Pt Cu纳米催化剂。TEM观察结果显示Pt Cu纳米催化剂平均粒径为30 nm左右。根据XRD结果表明Pt Cu纳米催化剂是一种面心立方结构。进一步的甲醇电催化氧化反应的催化性能表明:凹形树突状Pt-Cu双金属纳米晶体在电催化甲醇氧化的应用中表现出非常高的活性和很强的抗有毒中间体作用;根据If/Ib的数据对比发现,Pt Cu(2.76)纳米材料比商业Pt/C催化剂(1.02)具有更强的抗CO中毒能力。Pt Cu纳米催化剂的比活性和质量活性分别是商业Pt/C的1.95和2.04倍。
[Abstract]:Direct methanol fuel cell (DMFC) is a kind of proton exchange membrane fuel cell (PEMFC), which has the advantages of high energy conversion efficiency, simple structure and environmental friendliness. It is considered to be one of the most ideal removable energy sources.Up to now, Pt and Pt-based nanomaterials are still the most commonly used anode materials for direct methanol fuel cells. However, due to the high cost of Pt and less storage in nature, the commercialization of direct methanol fuel cells is seriously hindered.Therefore, it is urgent to study a new type of catalyst, which can reduce the amount of noble metal Pt and enhance the catalytic activity and stability of the catalyst.In this paper, the electrocatalytic oxidation of methanol over dendritic Pt-Au nanocatalysts and concave dendritic Pt-Cu alloy catalysts was studied.The specific research contents are as follows: (1) Pt nanocrystalline dendritic materials with uniform structure have been successfully synthesized by H _ 2 reduction method, and au has been successfully deposited on Pt NDs by solvothermal method.It was characterized by transmission electron microscopy (TEM) and X-ray diffraction (XRD) and EDX.Their catalytic properties for the redox reaction of methanol were measured by electrochemical method.The results show that Pt NDs and Pt-Au NHs have high electrochemical activity specific surface area and good electrochemical performance of methanol oxidation.The average particle size of the catalyst is about 30 nm.According to XRD results, Pt Cu nanocatalyst is a kind of face-centered cubic structure.The catalytic performance of further methanol electrocatalytic oxidation reaction showed that the concave dendritic Pt-Cu bimetallic nanocrystalline showed very high activity and strong anti-toxic intermediate in the application of electrocatalytic methanol oxidation;According to the data of If/Ib, it is found that the nano-materials of Pt-Cu-2.76) have stronger resistance to CO poisoning than commercial Pt/C catalysts. The specific activity and mass activity of Pt-Cu nano-catalysts are 1.95 and 2.04 times of commercial Pt/C, respectively.
【学位授予单位】：苏州大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TM911.4;TB383.1

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