铂钯基核壳型甲醇电催化剂的制备及其性能研究
发布时间：2018-11-09 16:39
【摘要】：碱性直接甲醇燃料电池(Alkaline Direct Methanol Fuel Cell,ADMFC)因具有能量密度高、来源丰富等特点而成为了研究者的关注热点。传统的直接甲醇燃料电池(Direct Methanol Fuel Cell,DMFC)阳极催化剂存在很多问题,如成本高、易中毒、电化学稳定性差等。所以,近阶段研究者对ADMFC阳极催化剂研究的主攻方向是提高催化剂活性和降低催化剂成本。基于以上对催化剂劣势的分析,本文通过优化的三相相转移法制备了PdPt基催化剂,并对PdPt基催化剂在碱性环境中的甲醇氧化反应进行了基础研究。本文改进了Cu@PdPt核壳催化剂的制备工艺,Cu@PdPt外壳前驱体比例等关键因素对催化剂催化性能的影响。在制备过程中考察了不同工艺参数(还原剂和中间相)对催化剂催化活性的影响,优化了Cu@PdPt催化剂的制备工艺,并分析其在碱性环境中性能明显提高的原因。通过实验数据分析,在PdPt前驱体在还原的过程中,还原剂的选择和中间相的存在能够影响实验的反应速率,从而改变Cu@PdPt核壳催化剂的催化性能。Cu@PdPt核壳催化剂的性能明显高于Pd Pt合金,分析其催化活性提高的主要原因为其内核Cu颗粒与外壳PdPt金属之间的电子相互作用。为了进一步验证三相相转移法能够制备核壳结构催化剂,并将Ni基作为核壳结构催化剂内核,采用三相相转移法制备了Ni@PdPt核壳结构催化剂。实验结果表明:在碱性环境中,Ni@PdPt催化剂比PdPt合金催化剂对甲醇氧化的催化性能提高3.62倍。XPS测试结果表明:内核Ni与PdPt外壳之间存在着强烈的电子相互作用,从而使核壳结构催化剂催化活性得到明显提高。
[Abstract]:Alkaline direct methanol fuel cell (Alkaline Direct Methanol Fuel Cell,ADMFC) has become a hot topic for its high energy density and abundant sources. Traditional (Direct Methanol Fuel Cell,DMFC anode catalysts for direct methanol fuel cell (DMFC) have many problems, such as high cost, easy poisoning, poor electrochemical stability and so on. Therefore, the research direction of the recent research on ADMFC anode catalyst is to improve the catalyst activity and reduce the catalyst cost. Based on the above analysis of the disadvantages of the catalyst, the PdPt based catalyst was prepared by the optimized three-phase transfer method, and the methanol oxidation reaction of the PdPt based catalyst in alkaline environment was studied. In this paper, the preparation process of Cu@PdPt core-shell catalyst and the effect of several key factors such as the precursor ratio of Cu@PdPt shell on the catalytic performance of the catalyst have been improved. The effects of different process parameters (reductant and mesophase) on the catalytic activity of Cu@PdPt catalyst were investigated. The preparation process of Cu@PdPt catalyst was optimized and the reasons for its performance improvement in alkaline environment were analyzed. Through the analysis of experimental data, the selection of reductant and the existence of mesophase can influence the reaction rate of PdPt precursor in the process of reduction. Therefore, the catalytic performance of Cu@PdPt core-shell catalyst is changed. The catalytic activity of Cu@PdPt core-shell catalyst is obviously higher than that of Pd Pt alloy. The main reason for the improvement of the catalytic activity is the electronic interaction between the core Cu particles and the shell PdPt metal. In order to further verify that the core-shell structure catalyst can be prepared by three-phase transfer method, and using Ni as the core of core-shell structure catalyst, Ni@PdPt core-shell structure catalyst was prepared by three-phase transfer method. The experimental results show that the catalytic performance of Ni@PdPt catalyst for methanol oxidation is 3.62 times higher than that of PdPt alloy catalyst in alkaline environment. The results of XPS test show that there is a strong electronic interaction between the core Ni and the shell of PdPt. Thus, the catalytic activity of the core-shell structure catalyst was obviously improved.
【学位授予单位】：黑龙江大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TQ426;TM911.4
，
本文编号：2320979
[Abstract]:Alkaline direct methanol fuel cell (Alkaline Direct Methanol Fuel Cell,ADMFC) has become a hot topic for its high energy density and abundant sources. Traditional (Direct Methanol Fuel Cell,DMFC anode catalysts for direct methanol fuel cell (DMFC) have many problems, such as high cost, easy poisoning, poor electrochemical stability and so on. Therefore, the research direction of the recent research on ADMFC anode catalyst is to improve the catalyst activity and reduce the catalyst cost. Based on the above analysis of the disadvantages of the catalyst, the PdPt based catalyst was prepared by the optimized three-phase transfer method, and the methanol oxidation reaction of the PdPt based catalyst in alkaline environment was studied. In this paper, the preparation process of Cu@PdPt core-shell catalyst and the effect of several key factors such as the precursor ratio of Cu@PdPt shell on the catalytic performance of the catalyst have been improved. The effects of different process parameters (reductant and mesophase) on the catalytic activity of Cu@PdPt catalyst were investigated. The preparation process of Cu@PdPt catalyst was optimized and the reasons for its performance improvement in alkaline environment were analyzed. Through the analysis of experimental data, the selection of reductant and the existence of mesophase can influence the reaction rate of PdPt precursor in the process of reduction. Therefore, the catalytic performance of Cu@PdPt core-shell catalyst is changed. The catalytic activity of Cu@PdPt core-shell catalyst is obviously higher than that of Pd Pt alloy. The main reason for the improvement of the catalytic activity is the electronic interaction between the core Cu particles and the shell PdPt metal. In order to further verify that the core-shell structure catalyst can be prepared by three-phase transfer method, and using Ni as the core of core-shell structure catalyst, Ni@PdPt core-shell structure catalyst was prepared by three-phase transfer method. The experimental results show that the catalytic performance of Ni@PdPt catalyst for methanol oxidation is 3.62 times higher than that of PdPt alloy catalyst in alkaline environment. The results of XPS test show that there is a strong electronic interaction between the core Ni and the shell of PdPt. Thus, the catalytic activity of the core-shell structure catalyst was obviously improved.
【学位授予单位】：黑龙江大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TQ426;TM911.4
，
本文编号：2320979
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