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通过一种结合了CO辅助合成Pt_3Ni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Pt_3Ni纳米立方粒子核结构的Pt_3Ni@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Pt_3Ni@Pd/C催化剂,结果显示大部分Pt_3Ni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Pt_3Ni@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Pt_3Ni/C催化剂进行了比较。结果显示,由于Pt_3Ni@Pd/C的单原子层Pd壳的结构和所暴露出的Pd{100}族的晶面,Pt_3Ni@Pd/C催化剂具有优异的甲酸氧化电催化性能。与原Pt_3Ni/C催化剂相比较,Pt_3Ni@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,Pt_3Ni@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。
A Pt_3Ni @ Pd / Pt nanoparticle with single atomic layer Pd shell and Pt_3Ni nano-cubic particle structure was successfully prepared by a method combining CO-assisted synthesis of Pt_3Ni nano-cubic particles and monatomic Cu shell underpotential deposition and then Pd substitution. C catalyst. Inductively coupled plasma atomic emission spectroscopy, X-ray diffraction and transmission electron microscopy were used to characterize the Pt 3 NiPd / C catalysts. The results showed that the surface of most Pt 3 Ni nanoparticles consisted of {100} crystal planes. Also on these {100} family of crystal planes, the monatomic Pd shell is epitaxially grown by electrodeposition and the {100} family of crystal planes are also obtained. The performance of Pt_3Ni @ Pd / C as a formic acid oxidation catalyst was further studied and compared with commercial Pd / C and Pt_3Ni / C catalysts. The results show that the Pt 3 NiPd / C catalyst has excellent formic acid oxidation electrocatalytic activity due to the structure of the Pd shell of Pt 3 NiPd / C and the exposed Pd {100} family of crystal planes. Compared with the original Pt_3Ni / C catalyst, the Pt_3Ni @ Pd / C catalyst showed a 7.5-fold increase in the noble metal mass-specific activity. In addition, the specific surface activity and Pd mass specific activity of Pt3Ni @ Pd / C catalyst were also increased to 2.5 and 8.3 times, respectively, compared with commercial Pd / C catalysts.