Zhang Lei, Chen Qiaoli, Wang Xue, Jiang Zhiyuan
Key Laboratory for Green Chemical Technology of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China.
State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.
Nanoscale. 2016 Feb 7;8(5):2819-25. doi: 10.1039/c5nr08154h.
The Au-Pd alloy has been proved to be an excellent catalyst in many applications, such as the electro-oxidation of formic acid, CO oxidation and oxidation of alcohols to aldehydes. However, most of the research has been focused on the shape-controlled Au-Pd alloy NCs with a single-crystal structure. Due to the existence of high-energy atoms on the twin defects, twinned structures usually will further increase their catalytic activities. It is necessary to develop a method to prepare the Au-Pd alloy with twinned structures and investigate their catalytic properties. Herein, we successfully synthesized Au-Pd alloy tripods and bipyramids with twinned structures by the cooperation of cetyltrimethyl ammonium chloride (CTAC) and cetyltrimethyl ammonium bromide (CTAB). The tripods contain one twin plane, while the bipyramids consist of a fivefold-twinned structure. In addition, the tripods and bipyramids are both exposed by high-energy facets. We proposed that the tripods and bipyramids are evolved from bipyramid seeds and fivefold twinned seeds, respectively. The as-prepared Au-Pd tripods and bipyramids performed better activity for electrocatalytic oxidation of formic acid compared to the cubic Au-Pd nanoparticles.
金钯合金已被证明在许多应用中是一种优异的催化剂，例如甲酸的电氧化、一氧化碳氧化以及醇氧化为醛。然而，大多数研究都集中在具有单晶结构的形状可控的金钯合金纳米晶上。由于孪晶缺陷上存在高能原子，孪晶结构通常会进一步提高其催化活性。有必要开发一种制备具有孪晶结构的金钯合金的方法，并研究其催化性能。在此，我们通过十六烷基三甲基氯化铵（CTAC）和十六烷基三甲基溴化铵（CTAB）的协同作用成功合成了具有孪晶结构的金钯合金三脚架和双锥体。三脚架包含一个孪晶面，而双锥体由五重孪晶结构组成。此外，三脚架和双锥体都由高能面暴露。我们提出三脚架和双锥体分别由双锥体种子和五重孪晶种子演化而来。与立方金钯纳米颗粒相比，所制备的金钯三脚架和双锥体对甲酸的电催化氧化表现出更好的活性。
