Pt基催化剂的制备及在甲醇电化学氧化中的应用研究
发布时间：2018-12-15 07:41
【摘要】：近年来,直接甲醇燃料电池阳极Pt基催化剂的研究受到了广泛关注。Pt催化剂被认为是最有效的甲醇燃料电池催化剂,但因其资源稀缺、价格昂贵、且容易吸附中间产物CO而中毒失活,制约了燃料电池的发展。第二种金属(如Ru、Rh、Sn、Ni、Co等)的加入,不仅可改变Pt的表面电学性质,还可在较低电势下提供含氧物种,增强其抗CO毒化能力,从而提高催化剂的活性和稳定性,此外,还可减少Pt的用量,降低催化剂成本。本论文以混酸(HF与HNO3)刻蚀法制得的高比表面积的刻蚀碳化硅(SiCetched)为基底,以H2PtCl6·2H2O、NiCl2·6H2O、CoCl2·6H2O为前驱物,通过化学还原法制备了一系列PtNi/SiCetched、PtCo/SiCetched型双金属催化剂,研究了不同PtN、PtCo比例对催化剂在甲醇电氧化中催化性能的影响；此外,以SiCetched和掺锑氧化锡(antimony tin oxide, ATO)混合物为基底,制备了不同ATO加入量的Pt基催化剂,研究了基底中ATO的加入量对催化剂的甲醇催化性能的影响。本论文共分为六章,主要研究内容及结论如下：第一章主要从Pt基催化剂的活性组分和载体两方面,对直接甲醇燃料电池(DMFC)阳极催化剂的研究进展进行综述,并介绍了本论文的选题意义、研究内容和创新点。第二章对本论文所用到的实验仪器,药品以及催化剂的制备、表征方法等进行了详细说明。第三章以SiCetched为载体,制备了一系列不同摩尔比的PtNi/SiCetched催化剂,通过UV、XRD、TEM、CV和CA手段对催化剂进行表征。结果表明,PtNi/SiCetched催化剂在焙烧过程中,Ni会掺杂到Pt的面心立方晶格中,形成PtNi合金,当n(Pt):n(Ni)=3时,PtNi/SiCetched催化剂对甲醇电氧化的催化活性最好,电流密度是Pt/SiCetched型催化剂的3倍左右,Ni的加入可以明显的改善Pt催化剂的催化活性和稳定性。第四章以SiCetched为载体,制备了PtCo/SiCetahed催化剂,然后用XRD、 TEM、CV和CA手段对其表征。结果表明,当n(Pt):n(Co)=1时,PtCo/SiCetehed型催化剂对甲醇的催化活性和稳定性最好,Pt-Co合金可以削弱Pt-CO键的强度,改善催化剂的抗CO中毒能力。第五章以掺杂ATO的SiCetched为复合载体,制备了不同基底的Pt基催化剂：Pt/SiCetched、Pt/(SiCetched+ATO)和Pt/ATO。通过电化学方法对其进行了表征,研究了复合载体中ATO与SiCetched的比例对催化效果的影响。研究结果表明,与Pt/SiCetetched、 Pt/ATO型催化剂相比,以复合材料为载体得到的Pt/(SiCetched+ATO)催化剂对甲醇电氧化的催化效果最好,说明ATO的加入有效的提高了催化剂的稳定性。第六章对本论文进行了总结,并提出了论文中亟待解决的问题及展望。
[Abstract]:In recent years, the research of direct methanol fuel cell anode Pt catalyst has received extensive attention. Pt catalyst is considered as the most effective methanol fuel cell catalyst, but its resource is scarce and the price is expensive. Moreover, it is easy to adsorb intermediate product CO and become toxic and inactivated, which restricts the development of fuel cell. The addition of the second metal (such as Ru,Rh,Sn,Ni,Co, etc.) can not only change the surface electrical properties of Pt, but also provide oxygen-containing species at lower potential, and enhance its ability to resist CO poisoning, thus improving the activity and stability of the catalyst. In addition, the amount of Pt can be reduced and the cost of catalyst reduced. In this paper, a series of PtNi/SiCetched, was prepared by chemical reduction method using high specific surface area etching silicon carbide (SiCetched) prepared by mixed acid (HF and HNO3) etching method and H2PtCl6 2H 2O NiCl 26 H 2O CoCl 2 6H2O as precursor. The effects of different PtN,PtCo ratios on the catalytic performance of PtCo/SiCetched bimetallic catalysts in methanol electrooxidation were studied. In addition, based on the mixture of SiCetched and antimony doped tin oxide (antimony tin oxide, ATO), different amount of ATO based catalysts were prepared. The effect of the amount of ATO in the substrate on the catalytic performance of methanol was studied. This thesis is divided into six chapters. The main research contents and conclusions are as follows: in chapter 1, the research progress of (DMFC) anode catalyst for direct methanol fuel cell (DMFC) is reviewed from the aspects of active component and support of (DMFC) catalyst. It also introduces the significance, research content and innovation of this paper. In the second chapter, the experimental instruments, preparation and characterization methods of drugs and catalysts are described in detail. In chapter 3, a series of PtNi/SiCetched catalysts with different molar ratios were prepared using SiCetched as the support. The catalysts were characterized by UV,XRD,TEM,CV and CA. The results show that during the calcination of PtNi/SiCetched catalyst, Ni will be doped into the face centered cubic lattice of Pt to form PtNi alloy. When n (Pt): n (Ni) = 3, the catalytic activity of PtNi/SiCetched catalyst for methanol electrooxidation is the best. The current density is about 3 times of that of Pt/SiCetched catalyst. The addition of Ni can obviously improve the catalytic activity and stability of Pt catalyst. In chapter 4, PtCo/SiCetahed catalyst was prepared on SiCetched and characterized by XRD, TEM,CV and CA. The results showed that when n (Pt): n (Co) = 1, the catalytic activity and stability of PtCo/SiCetehed type catalyst for methanol was the best, and Pt-Co alloy could weaken the strength of Pt-CO bond and improve the resistance to CO poisoning of the catalyst. In chapter 5, using SiCetched doped with ATO as composite support, different substrates of Pt based catalysts, Pt/SiCetched,Pt/ (SiCetched ATO) and Pt/ATO., were prepared. The effect of the ratio of ATO to SiCetched on the catalytic performance was studied by electrochemical method. The results showed that compared with the Pt/SiCetetched, Pt/ATO catalyst, the Pt/ (SiCetched ATO) catalyst supported on the composite material had the best catalytic effect on methanol electrooxidation, which indicated that the addition of ATO could effectively improve the stability of the catalyst. The sixth chapter summarizes this paper, and puts forward the problems and prospects to be solved.
【学位授予单位】：山西大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：O643.36;TM911.4
本文编号：2380273
[Abstract]:In recent years, the research of direct methanol fuel cell anode Pt catalyst has received extensive attention. Pt catalyst is considered as the most effective methanol fuel cell catalyst, but its resource is scarce and the price is expensive. Moreover, it is easy to adsorb intermediate product CO and become toxic and inactivated, which restricts the development of fuel cell. The addition of the second metal (such as Ru,Rh,Sn,Ni,Co, etc.) can not only change the surface electrical properties of Pt, but also provide oxygen-containing species at lower potential, and enhance its ability to resist CO poisoning, thus improving the activity and stability of the catalyst. In addition, the amount of Pt can be reduced and the cost of catalyst reduced. In this paper, a series of PtNi/SiCetched, was prepared by chemical reduction method using high specific surface area etching silicon carbide (SiCetched) prepared by mixed acid (HF and HNO3) etching method and H2PtCl6 2H 2O NiCl 26 H 2O CoCl 2 6H2O as precursor. The effects of different PtN,PtCo ratios on the catalytic performance of PtCo/SiCetched bimetallic catalysts in methanol electrooxidation were studied. In addition, based on the mixture of SiCetched and antimony doped tin oxide (antimony tin oxide, ATO), different amount of ATO based catalysts were prepared. The effect of the amount of ATO in the substrate on the catalytic performance of methanol was studied. This thesis is divided into six chapters. The main research contents and conclusions are as follows: in chapter 1, the research progress of (DMFC) anode catalyst for direct methanol fuel cell (DMFC) is reviewed from the aspects of active component and support of (DMFC) catalyst. It also introduces the significance, research content and innovation of this paper. In the second chapter, the experimental instruments, preparation and characterization methods of drugs and catalysts are described in detail. In chapter 3, a series of PtNi/SiCetched catalysts with different molar ratios were prepared using SiCetched as the support. The catalysts were characterized by UV,XRD,TEM,CV and CA. The results show that during the calcination of PtNi/SiCetched catalyst, Ni will be doped into the face centered cubic lattice of Pt to form PtNi alloy. When n (Pt): n (Ni) = 3, the catalytic activity of PtNi/SiCetched catalyst for methanol electrooxidation is the best. The current density is about 3 times of that of Pt/SiCetched catalyst. The addition of Ni can obviously improve the catalytic activity and stability of Pt catalyst. In chapter 4, PtCo/SiCetahed catalyst was prepared on SiCetched and characterized by XRD, TEM,CV and CA. The results showed that when n (Pt): n (Co) = 1, the catalytic activity and stability of PtCo/SiCetehed type catalyst for methanol was the best, and Pt-Co alloy could weaken the strength of Pt-CO bond and improve the resistance to CO poisoning of the catalyst. In chapter 5, using SiCetched doped with ATO as composite support, different substrates of Pt based catalysts, Pt/SiCetched,Pt/ (SiCetched ATO) and Pt/ATO., were prepared. The effect of the ratio of ATO to SiCetched on the catalytic performance was studied by electrochemical method. The results showed that compared with the Pt/SiCetetched, Pt/ATO catalyst, the Pt/ (SiCetched ATO) catalyst supported on the composite material had the best catalytic effect on methanol electrooxidation, which indicated that the addition of ATO could effectively improve the stability of the catalyst. The sixth chapter summarizes this paper, and puts forward the problems and prospects to be solved.
【学位授予单位】：山西大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：O643.36;TM911.4
【参考文献】
相关期刊论文 前1条
1 ;Carbon nanotubes-Nafion composites as Pt-Ru catalyst support for methanol electro-oxidation in acid media[J];Journal of Natural Gas Chemistry;2009年02期
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