Methanol oxidation catalysis and substructure of PtRu/C bimetallic nanoparticles synthesized by a radiolytic process
Methanol oxidation catalysis and substructure of PtRu/C bimetallic nanoparticles synthesized by a radiolytic process
复制标题
DOI：
10.1016/j.apcata.2011.01.037
复制
发表时间：
2011-04-15
影响因子：
5.5
通讯作者：
Daimon, Hideo
中科院分区：
文献类型：
--
作者：
Yamamoto, Takao A.;Kageyama, Satoru;Daimon, Hideo
采用辐解法制备了直接甲醇燃料电池阳极PtRu/C纳米催化剂。通过改变辐照剂量率和添加NH 4 OH或NaH 2 PO 2来控制双金属亚结构。利用透射电子显微镜、X射线衍射、X射线荧光光谱和X射线吸收精细结构技术对材料进行了表征。采用线性扫描伏安法对甲醇氧化活性进行了评价。我们的结论是，辐射合成的催化剂的结构具有富Pt的核/富Ru的壳结构或不完全的合金结构。通过扩展X射线吸收精细结构分析确定的配位数定义的配对因子发现亚结构和催化活性之间的相关性，这表明PtRu纳米颗粒体系中双功能机制的有效性。这种辐解过程是有希望的合成先进的PtRu/C催化剂，具有良好的混合的亚结构，提高甲醇氧化。(C)2011 Elsevier B. V.保留所有权利。
Nanoparticle catalysts of PtRu/C for the direct methanol fuel cell anode were synthesized by a radiolytic process. Bimetallic substructures were controlled by varying irradiation dose rate and by addition of NH4OH or NaH2PO2. Material characterization was performed with the transmission electron microscopy, the X-ray diffraction, the X-ray fluorescence spectroscopy and the X-ray absorption fine structure techniques. Methanol oxidation activity was evaluated by the linear sweep voltammetry. We concluded that the structure of the radiolytically synthesized catalysts has a Pt-rich core/Ru-rich shell structure or incomplete alloy structure. A correlation between the substructures and catalytic activities was found by using a pairing factor defined from coordination numbers determined by the extend X-ray absorption fine structure analysis, which indicates the validity of the bifunctional mechanism in the PtRu nanoparticle system. This radiolytic process is promising for synthesizing advanced PtRu/C catalysts with well-mixed bimetallic substructures enhancing methanol oxidation. (C) 2011 Elsevier B.V. All rights reserved.