低铂多组分燃料电池催化剂的制备及其性能研究

发布时间：2018-04-20 00:00

本文选题：燃料电池催化剂 + 三翼结构　；参考：《哈尔滨工业大学》2014年硕士论文

【摘要】：能源是人类社会赖以生存和发展的重要的物质基础。当前，人们日常生活、工业生产所需要的能源主要来自于煤、石油、天然气等传统不可再生化石能源。但其不可再生且地球储存量有限，同时传统热机在实现化学能向热能、电能等能量转化的时候受到卡诺循环的限制，因此对于能源的利用率比较低，并且对环境污染严重。燃料电池技术因其低污染、高效率、用途广、燃料来源广泛等优点在寻求用于替代传统化石燃料的新技术过程中，日益得到关注。目前用于燃料电池使用的催化剂是商用的铂催化剂，但是铂催化剂存在主要问题：（1）贵金属铂的使用价格昂贵且资源稀缺，导致了燃料电池的制作成本很高，因此需要进一步的降低铂的含量，同时提高催化剂的活性；（2）一些中间产物如CO会在甲醇过程中吸附在催化剂表面影响催化性能，需通过调控催化剂的形貌结构和种类，从而提高催化剂的性能和性能的稳定性；（3）开发寻求合理的制备催化剂的合成方法，使其成本低廉、工艺简单并且容易控制的催化剂。以上三个问题成为制约燃料电池商业化进程的重要因素。本论文针对以上的三个问题，通过牺牲模板原位还原的方法制备了铂含量低、结构特殊且稳定的具有高催化性能的碲铂钯催化剂。同时通过调控其组分含量和形貌结构在降低铂的含量的同时，提高催化剂的催化性能和稳定性，并且探讨了催化剂材料的应用前景。主要内容如下：（1）首先利用水热合成法合成了一维的具有三翼特殊结构和长条结构的还原性材料碲，将其作为牺牲模板和还原剂，用原位还原的方法在保证原模板形貌和结构的同时，，合成了具有三翼结构和长条结构的碲铂钯三组分催化剂。（2）探讨了不同组分（二元组分Te53Pt47和三元组分Te62Pt11Pd27）三翼结构的催化剂以及不同比例元素含量的Te53Pt10Pd33、Te62Pt11Pd27以及Te62Pt20Pd18三翼结构材料对于燃料电池催化剂的催化性能以及稳定性能的不同影响。通过电化学性能测试，发现合成的三组分Te62Pt11Pd27催化剂的催化性能优异，其活性表面积是商用的铂碳的1.5倍，同时对于甲醇的催化氧化也展示了很好的催化性能。（3）在制备这样具有特殊结构催化剂的过程中，通过调控催化剂中的形貌结构，即长条结构和三翼结构的碲铂钯催化剂，对于电化学特性和甲醇氧化（MOR）催化性能和稳定性的影响。发现具有相同成分的不同结构，其催化活性也有一定的差异。三翼结构的碲铂钯相对于长条结构具有更优的催化性能。
[Abstract]:Energy is an important material basis for the survival and development of human society. At present, people's daily life, industrial production needs energy mainly from coal, oil, natural gas and other traditional non-renewable fossil energy. But it is non-renewable and the storage of the earth is limited. At the same time, the traditional heat engine is restricted by the Carnot cycle when realizing the energy conversion from chemical energy to heat energy and electric energy. Therefore, the utilization rate of energy is relatively low and the pollution to the environment is serious. Because of its advantages of low pollution, high efficiency, wide application and wide range of fuel sources, fuel cell technology has attracted more and more attention in the process of seeking new technologies to replace traditional fossil fuels. At present, the catalysts used in fuel cells are commercial platinum catalysts, but there is a major problem with platinum catalysts. (the expensive use of precious metal platinum and the scarcity of resources lead to the high cost of manufacturing fuel cells. Therefore, it is necessary to further reduce the content of platinum and increase the activity of the catalyst.) some intermediate products such as CO adsorbed on the surface of the catalyst in the methanol process will affect the catalytic performance by regulating the morphology, structure and type of the catalyst. In order to improve the performance and stability of the catalyst, we can develop a reasonable synthesis method to make the catalyst cheap, simple and easy to control. The above three problems have become an important factor restricting the commercialization of fuel cells. In order to solve the above three problems, the platinum catalyst with low platinum content, special structure and high catalytic performance was prepared by sacrificial template in situ reduction. At the same time, the catalytic performance and stability of the catalyst were improved by adjusting the composition and morphology of the catalyst, and the application prospect of the catalyst material was also discussed. The main contents are as follows: Firstly, one dimensional reductive material tellurium with three-wing special structure and long strip structure was synthesized by hydrothermal synthesis method, which was used as sacrificial template and reductant. The original template morphology and structure were guaranteed by in-situ reduction method. Three component catalysts of platinum and palladium tellurium with three wing structure and long strip structure were synthesized. The effects of different components (binary component Te53Pt47 and ternary component Te62Pt11Pd27) on the catalytic performance and stability of fuel cell catalysts were investigated. The electrochemical performance test showed that the synthesized Te62Pt11Pd27 catalyst had excellent catalytic performance, and its active surface area was 1.5 times that of commercial platinum carbon. At the same time, it also showed good catalytic performance for the catalytic oxidation of methanol. During the preparation of the catalyst with such a special structure, the effect of the morphology of the catalyst, that is, the strip structure and the three-wing structure, on the electrochemical characteristics and the catalytic performance and stability of methanol oxidation mor is regulated. It was found that the catalytic activity of different structures with the same composition was also different. The catalytic performance of three-wing platinum-palladium tellurium is better than that of long strip structure.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：O643.36;TM911.4

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