Abstract Using an embedding atom method, the low-lying candidate structures of a large Pt-Cu alloy cluster Pt86Cu22 were obtained through screening 105 isomers. The results indicate that the Pt@PtCu core-shell structures with Pt skin and PtCu core are energetically more stable than the others, which is in good agreement with the experimental observation. Furthermore, an impurity Cu atom is preferred to stay at the subsurface instead of the surface region of Pt-Cu alloy clusters, and the doped Cu atoms prefer to disperse in Pt-Cu alloy. The electronic structures of the EAM optimized structures are calculated with density functional theory, and the projected electronic densities of states reveal that Cu doping can obviously enrich the electronic states of surface Pt atoms near the Fermi level, which may provide some clues for understanding the mechanism of enhancement of the catalytic activity for Pt-Cu alloy catalyst.

中文翻译：

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Pt-Cu合金团簇的结构和电子特性：嵌入原子法结合密度泛函理论研究

摘要 采用嵌入原子法，筛选了105个异构体，得到了大Pt-Cu合金团簇Pt86Cu22的低位候选结构。结果表明，具有 Pt 表皮和 PtCu 核的 Pt@PtCu 核壳结构在能量上比其他结构更稳定，这与实验观察结果一致。此外，杂质Cu原子优选留在亚表面而不是Pt-Cu合金簇的表面区域，并且掺杂的Cu原子更倾向于分散在Pt-Cu合金中。EAM优化结构的电子结构用密度泛函理论计算，状态的投影电子密度表明Cu掺杂可以明显丰富费米能级附近的表面Pt原子的电子态，