物理化学学报 >> 2016, Vol. 32 >> Issue (1): 337-342.doi: 10.3866/PKU.WHXB201509144

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单原子层Pd壳的Pt3Ni纳米立方体的甲酸氧化性能

罗柳轩,沈水云,朱凤鹃,章俊良*()   

  • 收稿日期:2015-08-24 发布日期:2016-01-13
  • 通讯作者: 章俊良 E-mail:junliang.zhang@sjtu.edu.cn
  • 基金资助:
    国家自然科学基金(21373135);中国教育部科学基金(413064);高等学校学科创新引智计划(B13018)

Formic Acid Oxidation by Pd Monolayers on Pt3Ni Nanocubes

Liu-Xuan LUO,Shui-Yun SHEN,Feng-Juan ZHU,Jun-Liang ZHANG*()   

  • Received:2015-08-24 Published:2016-01-13
  • Contact: Jun-Liang ZHANG E-mail:junliang.zhang@sjtu.edu.cn
  • Supported by:
    the National Natural Science Foundation of China(21373135);Science Foundation of Ministry of Education of China(413064);Program of Introducing Talents of Discipline to Universities, China ("111 Project")(B13018)

摘要:

通过一种结合了CO辅助合成Pt3Ni纳米立方粒子和单原子层Cu壳欠电位沉积再置换为Pd的方法,成功制备出了具有单原子层Pd壳和Pt3Ni纳米立方粒子核结构的Pt3Ni@Pd/C催化剂。电感耦合等离子体元素分析、X射线衍射和透射电子显微镜法被用于研究表征此种Pt3Ni@Pd/C催化剂,结果显示大部分Pt3Ni纳米粒子的表面都由{100}族的晶面所构成。而且在这些{100}族的晶面上,单原子层Pd壳通过电沉积的外延生长,也获得了{100}族的晶面。本文进一步对Pt3Ni@Pd/C作为甲酸氧化电催化剂的性能进行了研究,并与商业Pd/C和原Pt3Ni/C催化剂进行了比较。结果显示,由于Pt3Ni@Pd/C的单原子层Pd壳的结构和所暴露出的Pd{100}族的晶面,Pt3Ni@Pd/C催化剂具有优异的甲酸氧化电催化性能。与原Pt3Ni/C催化剂相比较,Pt3Ni@Pd/C催化剂的贵金属质量比活性提高到了7.5倍。此外,与商业Pd/C催化剂相比,Pt3Ni@Pd/C催化剂的比表面活性和Pd质量比活性也分别提高到了2.5和8.3倍。

关键词: 电催化剂, 甲酸氧化, 单原子层Pd壳, 立方体结构, 核壳结构

Abstract:

We designed and synthesized carbon-supported cubic Pt3Ni nanoparticles (NPs) with Pd monolayer shells (Pt3Ni@Pd/C) by a two-step method: generally, CO-assisted preparation of cubic Pt3Ni NPs, Pd monolayer deposition through underpotential deposition of a Cu monolayer, and displacement of Cu with Pd. The as-synthesized Pt3Ni@Pd/C catalyst was characterized with inductively coupled plasma elemental analysis, X-ray diffraction, and transmission electron microscopy. Most Pt3Ni NPs had a cubic nanostructure enclosed by {100} facets, on which the Pd monolayer shells were deposited epitaxially via electrodeposition, by which the Pd monolayers gained the crystallographic orientation of the {100} facets. We then used Pt3Ni@Pd/C as an electrocatalyst for formic acid oxidation (FAO), comparing it with commercial Pd/C and the pristine Pt3Ni/C catalysts. The Pt3Ni@Pd/C exhibited superior electrocatalytic performance because of its monolayer structure and exposed Pd{100} facets. The noble-metal mass activity of the Pt3Ni/C with the deposited Pd monolayer shell was 7.5 times greater than that of the Pt3Ni/C catalyst alone. Moreover, the area-specific and Pd mass activities of Pt3Ni@Pd/C were 2.5 and 8.3 times greater than those of the commercial Pd/C catalyst, respectively.

Key words: Electrocatalyst, Formic acid oxidation, Palladium monolayer, Cubic structure, Core-shell structure

MSC2000: 

  • O646