通过硅氢加成反应合成铂钌纳米颗粒及其作为直接甲醇燃料电池催化剂的应用。

Synthesis of PtRu nanoparticles from the hydrosilylation reaction and application as catalyst for direct methanol fuel cell.

作者信息

Huang Junchao, Liu Zhaolin, He Chaobin, Gan Leong Ming

机构信息

Institute of Materials Research and Engineering (IMRE), 3 Research Link, Singapore 117602.

出版信息

J Phys Chem B. 2005 Sep 8;109(35):16644-9. doi: 10.1021/jp052667j.

DOI:10.1021/jp052667j

PMID:16853117

Abstract

Nanosized Pt, PtRu, and Ru particles were prepared by a novel process, the hydrosilylation reaction. The hydrosilylation reaction is an effective method of preparation not only for Pt particles but also for other metal colloids, such as Ru. Vulcan XC-72 was selected as catalyst support for Pt, PtRu, and Ru colloids, and TEM investigations showed nanoscale particles and narrow size distribution for both supported and unsupported metals. All Pt and Pt-rich catalysts showed the X-ray diffraction pattern of a face-centered cubic (fcc) crystal structure, whereas the Ru and Ru-rich alloys were more typical of a hexagonal close-packed (hcp) structure. As evidenced by XPS, most Pt and Ru atoms in the nanoparticles were zerovalent, except a trace of oxidation-state metals. The electrooxidation of liquid methanol on these catalysts was investigated at room temperature by cyclic voltammetry and chronoamperometry. The results concluded that some alloy catalysts showed higher catalytic activities and better CO tolerance than the Pt-only catalyst; Pt56Ru44/C have displayed the best electrocatalytic performance among all carbon-supported catalysts.

摘要

通过一种新的方法——硅氢加成反应制备了纳米尺寸的铂、铂钌和钌颗粒。硅氢加成反应不仅是制备铂颗粒的有效方法，也是制备其他金属胶体（如钌）的有效方法。选用Vulcan XC - 72作为铂、铂钌和钌胶体的催化剂载体，透射电子显微镜（TEM）研究表明，负载型和非负载型金属均呈现纳米级颗粒且尺寸分布狭窄。所有铂和富铂催化剂均呈现面心立方（fcc）晶体结构的X射线衍射图谱，而钌和富钌合金更典型地呈现六方密堆积（hcp）结构。X射线光电子能谱（XPS）证明，纳米颗粒中的大多数铂和钌原子为零价，除了微量的氧化态金属。通过循环伏安法和计时电流法在室温下研究了这些催化剂上液态甲醇的电氧化。结果表明，一些合金催化剂比纯铂催化剂表现出更高的催化活性和更好的抗一氧化碳耐受性；Pt56Ru44/C在所有碳载催化剂中表现出最佳的电催化性能。