PtRu/C电催化剂上甲醇吸附氧化过程的电化学原位红外光谱  

In situ Electrochemical FTIR Spectroscopy of Adsorption and Oxidation Process of Methanol on PtRu/C Electrocatalyst

作　　者：王琪[1] 孙公权[1] 闫世友[1] 汪国雄[1] 辛勤[1] 陈青松[2] 李君涛[2] 姜艳霞[2] 孙世刚[2] 

机构地区：[1]中国科学院大连化学物理研究所 [2]厦门大学化学系固体表面物理化学国家重点实验室,厦门361005

出　　处：《高等学校化学学报》2006年第11期2123-2127,共5页Chemical Journal of Chinese Universities

基　　金：厦门大学固体表面物理化学国家重点实验室开放课题(批准号:200304)资助

摘　　要：采用调变的多元醇法制备了高分散的Pt/C,PtRu/C和Ru/C电催化剂.XRD计算结果表明,PtRu/C电催化剂的平均粒径和合金度分别为2.2 nm和71%.采用电化学方法和原位傅里叶变换红外反射光谱方法(in situFTIRS)研究了甲醇在3种电催化剂上的吸附氧化过程,发现PtRu/C对甲醇的催化活性明显高于Pt/C,Ru的加入一方面影响了甲醇在Pt上的解离吸附性能,另一方面提供了Ru-OH物种,从而抑制了低电位下电催化剂中毒.红外光谱研究结果表明,线性吸附态CO(COL)是主要毒化物种,反应产物主要是CO2,还有少量的甲酸甲酯.根据实验结果讨论了甲醇在PtRu/C电催化剂上的氧化机理.A modified polyol process was used to prepare Pt/C, PtRu/C and Ru/C electrocatalysts. Calculated from XRD patterns, the mean particle size of PtRu/C electrocatalyst was 2.2 nm and the percentage of Ru alloyed was 71%, respectively. Adsorption and electro-oxidation progress of methanol on PtRu/C electrocatalyst was investigated by in situ FTIRS, combined with electrochemical experiments. It is revealed that the activity of PtRu/C electrocatalyst for methanol oxidation was much higher titan that of Pt/C. Addition of Ru in PtRu/C electrocatalyst changed the characteristic of methanol adsorption, and Ru-OH species could oxidize linear bonded CO （ COL） at a lower potential, thus inhibited the catalyst poisoning. In addition, from FTIRs results, COL was evidently identified to the main poisonous species and the major product was CO2. Methyl formate was also identified. Based on these results, the mechanism of methanol oxidation was discussed.

关 键 词：直接甲醇燃料电池 PTRU/C 甲醇氧化 电化学 in SITU FTIRS 

分 类 号：O643.3[理学—物理化学] TM911.4[理学—化学]