铂基催化剂的制备及其电催化性能的研究

发布时间：2018-04-16 02:15

本文选题：甲醇氧化 + Pt基催化剂　；参考：《青岛科技大学》2017年硕士论文

【摘要】：直接甲醇燃料电池(DMFC)作为一种便携式电源,引起人们很大的研究兴趣。但其阳极催化剂成本高,活性低限制了DMFC商业化。本文针对这些问题,在提高催化剂活性,降低催化剂成本方面进行了以下几方面研究。首先,采用微波法制备了Pt/CNTs、PtRu/CNTs,用于催化甲醇氧化反应。研究发现在电极上Pt含量为12.75μg·cm-2,Nafion含量为55%时,Pt/CNTs催化甲醇氧化的活性最高。甲醇在Pt/CNTs上的氧化受扩散控制。PtRu催化剂的活性与粒径关系不明显,在Pt/Ru摩尔比为3/1时,催化甲醇氧化活性最高。其次,采用微波法制备了PtM/CNTs(M=Co、Sn、Cu、Fe、Ni),其中PtSn/CNTs平均粒径最小,催化甲醇氧化活性最高。分析发现PtSn/CNTs中Sn主要是以SnO2形式存在,少部分零价Sn与Pt形成合金。PtSn催化甲醇氧化的活性不仅与粒径有关,同时与Sn的存在形式有关。第三,采用抗坏血酸为还原剂制备PtPd/CNTs,由小粒子组成的PtPd纳米颗粒均匀地负载在CNTs上,PtPd纳米颗粒的平均粒径为68 nm。PtPd纳米颗粒具有合金相结构,Pt在颗粒表面富集。在催化剂制备过程中,NaOH、抗坏血酸和CTAB的加入量以及Pt/Pd摩尔比会影响催化剂的形貌。研究发现制备的PtPd/CNTs催化甲醇氧化的性能优异。
[Abstract]:As a portable power supply, direct methanol fuel cell (DMFC) has attracted much attention.However, the high cost of anode catalyst and low activity limit the commercialization of DMFC.In order to solve these problems, the following aspects have been studied in improving catalyst activity and reducing catalyst cost.Firstly, a microwave method was used to prepare PT / CNTsO / PtRu- / CNTs for the catalytic oxidation of methanol.It was found that Pt / CNTs had the highest catalytic activity for methanol oxidation when Pt content was 12.75 渭 g / cm ~ (-2) and Nafion content was 55 on the electrode.The oxidation of methanol on Pt/CNTs was controlled by diffusion. The activity of PtRu catalyst was not related to the particle size. When the molar ratio of Pt/Ru was 3 / 1, the catalytic activity of methanol oxidation was the highest.Secondly, the PtM / CNTsCU CoSnSnCU FeFeNiN was prepared by microwave method, in which the average particle size of PtSn/CNTs was the smallest, and the catalytic activity of methanol oxidation was the highest.It is found that Sn in PtSn/CNTs mainly exists in the form of SnO2, and the catalytic activity of a small part of Sn and Pt in methanol oxidation is not only related to the particle size, but also to the existence form of Sn.Thirdly, PtPd / CNTswere prepared by ascorbic acid as reducing agent. The average particle size of PtPd nanoparticles loaded on CNTs was 68 nm.PtPd nanoparticles with alloy phase structure and Pt enriched on the surface of CNTs.The amount of ascorbic acid and CTAB and the molar ratio of Pt/Pd will affect the morphology of the catalyst.It was found that the prepared PtPd/CNTs had excellent catalytic performance for methanol oxidation.
【学位授予单位】：青岛科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O643.36;TM911.4

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