中文摘要：

以多壁碳纳米管（MWCNTs）为载体,制备了Pt载量为20%的Pt-（RuOxHy）m/MWCNTs催化剂（m为Ru/Pt原子比）,在m≤0.4时考察了不同电势区间循环伏安预处理对其催化性能的影响.水合氧化钌（RuOxHy）的存在明显提高了Pt催化剂抗CO毒化的能力,而在甲醇电氧化反应中Pt的质量比活性（MSA）随样品中m值增大呈先升后降趋势.经低电势区间（-0.20-0.46 V vs SCE）预处理稳定的催化剂中,Pt-（RuOxHy）0.10/MWCNTs样品中Pt的甲醇电氧化反应的MSA提高至相应单组分Pt/MWCNTs的9倍.将预处理电势区间扩展到高电势（即-0.20-0.96 V vs SCE）会造成钌组分溶解流失,导致催化剂抗CO毒化能力下降.在经过高电势区间的预处理后,Pt-（RuOxHy）020/MWCNTs对甲醇电氧化反应呈现出最高的催化活性,为单组分Pt催化剂的1.4倍.这些结果证实,水合氧化钉是Pt电催化剂的有效助剂.

英文摘要：

A series of Pt-（RuOxHy）m/MWCNTs catalysts （m being the Ru/Pt atomic ratio） containing 20% Pt were prepared using multi-walled carbon nanotubes （MWCNTs） as the support. The activity towards CO and methanol electro-oxidation of Pt in these catalysts after repeated cyclic voltammetry treatments in low （-0.20-0.46 V vs SCE） and extended （-0.20-0.96 V vs SCE） potential regions was investigated. The results showed that the presence of hydrous ruthenium oxide （RuOxHy） significantly reduced the over-potential of CO electro-oxidation on Pt, and the activity of Pt in Pt-（RuOxHy）m/MWCNTs for methanol electro-oxidation could thus be maximized by proper tuning of m. After the treatment in the low potential region, the mass-specific activity （MSA） of Pt in Pt-（RuOxHy）m/MWCNTs of m = 0.10 for methanol electro-oxidation increased by nearly 9 times that in Pt/MWCNTs. Significant dissolution of RuOxHy species was detected after the pretreatment in the extended potential region, which resulted in reduced CO tolerance and changed the activity order of Pt-（RuOxHy）m/MWCNTs catalysts for methanol electro-oxidation. In this case, Pt in the sample with m = 0.20 showed the highest MSA, which was still 40% higher than that of Pt/MWCNTs.