Department of Chemistry and Biochemistry, The University of Texas at Austin, 1 University Station, A5300 Austin, Texas 78712-0165, USA.
J Am Chem Soc. 2012 Mar 7;134(9):4153-62. doi: 10.1021/ja209115e. Epub 2012 Feb 22.
The voltammetry of Cu underpotential deposition (UPD) onto Pt dendrimer-encapsulated nanoparticles (DENs) containing an average of 147 Pt atoms (Pt(147)) is correlated to density functional theory (DFT) calculations. Specifically, the voltammetric peak positions are in good agreement with the calculated energies for Cu deposition and stripping on the Pt(100) and Pt(111) facets of the DENs. Partial Cu shells on Pt(147) are more stable on the Pt(100) facets, compared to the Pt(111) facets, and therefore, Cu UPD occurs on the 4-fold hollow sites of Pt(100) first. Finally, the structures of Pt DENs having full and partial monolayers of Cu were characterized in situ by X-ray absorption spectroscopy (XAS). The results of XAS studies are also in good agreement with the DFT-optimized models.
Cu 在含平均 147 个 Pt 原子的 Pt 树状大分子封装纳米粒子 (DEN) 上的欠电位沉积 (UPD) 的伏安法与密度泛函理论 (DFT) 计算相关联。具体来说，伏安峰位置与 DEN 上 Pt(100) 和 Pt(111) 晶面的 Cu 沉积和剥离的计算能很好地吻合。与 Pt(111) 晶面相比，Pt(147) 上的部分 Cu 壳在 Pt(100) 晶面更稳定，因此，Cu UPD 首先在 Pt(100) 的四配位空位上发生。最后，通过 X 射线吸收光谱 (XAS) 对具有完整和部分单层 Cu 的 Pt DEN 进行了原位结构表征。XAS 研究的结果也与 DFT 优化模型很好地吻合。
