高催化活性金属纳米粒子制备及其性能研究

发布时间：2018-07-05 10:20

本文选题：铂纳米晶 + 催化剂　；参考：《浙江理工大学》2015年硕士论文

【摘要】：燃料电池是一种将化学能高效转化为电能的电化学装置，是解决当前能源危机的一种有效途径，受到广大科研人员的密切关注。电催化剂是决定燃料电池性能的关键因素之一。目前燃料电池中广泛使用的电催化剂的主要成分为贵金属铂纳米材料，这主要归咎于其优异的催化性能。但是铂的存储量少，价格昂贵，在实际催化过程中容易发生CO中毒，因此铂纳米催化剂催化性能的提高具有重要意义。本论文主要致力于制备高催化活性的铂纳米催化剂，并对它们的电催化性能进行研究。具体研究内容如下： 1、超支化铂纳米晶的制备及其电化学性能研究我们通过简易的液相化学还原法制备了超支化铂纳米晶催化剂：在室温环境下，以氯铂酸作为铂的前驱体，水和聚乙烯吡咯烷酮分别作为溶剂和表面活性剂，以抗坏血酸为还原剂。透射电子显微镜(TEM)的表征结果显示铂纳米晶呈现分散性良好的超支化结构。该催化剂在甲醇的电化学氧化反应中表现出良好的催化活性，其面积比活性是商业Pt/C催化剂的1.6倍。 2、八面体铂纳米簇的制备及其电化学性能研究我们通过简易的一步水热法制备了八面体铂纳米簇催化剂：在高温高压实验条件下，以水为溶剂，氯铂酸为铂的前驱体，葡萄糖为还原剂，，十六烷基三甲基溴化铵为结构诱导剂。透射电子显微镜(TEM)和场发射扫描电镜(FESEM)的表征结果显示铂纳米晶呈现分散性良好的八面体纳米簇结构。该催化剂在甲醇的电化学氧化反应中表现出良好的催化活性，其质量比活性是商业Pt/C催化剂的1.86倍。 3、一步法制备三维枝状铂纳米晶体我们通过简易的一步水热法制备了三维枝状铂纳米晶体催化剂：在高温高压实验条件下，以水为溶剂，氯铂酸为铂的前驱体，果糖为还原剂。透射电子显微镜(TEM)的表征结果显示铂纳米晶呈现分散性良好的三维枝状结构。该催化剂在甲醇的电化学氧化反应中表现出良好的催化活性，其质量比活性是商业Pt/C催化剂的2.5倍。
[Abstract]:Fuel cell is an electrochemical device which can efficiently convert chemical energy into electric energy. It is an effective way to solve the current energy crisis and has been paid close attention to by many researchers. Electrocatalyst is one of the key factors to determine the performance of fuel cells. At present, the main component of the widely used electrocatalysts in fuel cells is precious metal platinum nanomaterials, which is mainly attributed to their excellent catalytic performance. However, due to the small storage and high price of platinum, CO poisoning is easy to occur in the actual catalytic process, so it is of great significance to improve the catalytic performance of platinum nanocatalysts. In this thesis, platinum nanocatalysts with high catalytic activity were prepared and their electrocatalytic properties were studied. Preparation and Electrochemical Properties of Hyperbranched Platinum Nanocrystals; We prepared hyperbranched platinum nanocrystalline catalysts by a simple liquid-phase chemical reduction method: at room temperature, Chloroplatinic acid was used as precursor of platinum, water and polyvinylpyrrolidone as solvent and surfactant, ascorbic acid as reductant respectively. The results of transmission electron microscopy (TEM) show that platinum nanocrystals exhibit a well-dispersed hyperbranched structure. The catalyst exhibited good catalytic activity in the electrochemical oxidation of methanol. Preparation of octahedron platinum nanoclusters and their electrochemical properties; preparation of octahedron platinum nanoclusters and their electrochemical properties; preparation of octahedron platinum nanoclusters by a simple one-step hydrothermal method Agent: under the experimental conditions of high temperature and high pressure, Using water as solvent, chloroplatinic acid as precursor of platinum, glucose as reducing agent, cetyltrimethylammonium bromide as structure inducer. The results of transmission electron microscopy (TEM) and field emission scanning electron microscopy (FESEM) show that platinum nanocrystals exhibit good dispersion octahedron nanoclusters. The catalyst exhibited good catalytic activity in the electrochemical oxidation of methanol. Its mass specific activity is 1.86 times higher than that of commercial Pt / C catalysts. 3. 3. Three-dimensional dendritic platinum nanocrystals were prepared by one step method, and we prepared three dimensional dendritic platinum nanocrystalline catalysts by a simple one step hydrothermal method. Under the experimental conditions of high temperature and high pressure, Using water as solvent, chloroplatinic acid as precursor of platinum, fructose as reducing agent. The results of transmission electron microscopy (TEM) show that platinum nanocrystals exhibit a good dispersion of three-dimensional dendritic structure. The catalyst exhibited good catalytic activity in the electrochemical oxidation of methanol, and its mass specific activity was 2.5 times higher than that of commercial Pt / C catalyst.
【学位授予单位】：浙江理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：O643.36;TM911.4

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