Center of Advanced Nanocatalysis, University of Science and Technology of China (CAN-USTC), Hefei, Anhui, 230026, P.R. China.
Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui Province, 230026, P.R. China.
Angew Chem Int Ed Engl. 2016 Apr 25;55(18):5501-5. doi: 10.1002/anie.201601016. Epub 2016 Mar 24.
Herein, we report an epitaxial-growth-mediated method to grow face-centered cubic (fcc) Ru, which is thermodynamically unfavorable in the bulk form, on the surface of Pd-Cu alloy. Induced by the galvanic replacement between Ru and Pd-Cu alloy, a shape transformation from a Pd-Cu@Ru core-shell to a yolk-shell structure was observed during the epitaxial growth. The successful coating of the unconventional crystallographic structure is critically dependent on the moderate lattice mismatch between the fcc Ru overlayer and PdCu3 alloy substrate. Further, both fcc and hexagonal close packed (hcp) Ru can be selectively grown through varying the lattice spacing of the Pd-Cu substrate. The presented findings provide a new synthetic pathway to control the crystallographic structure of metal nanomaterials.
在此，我们报告了一种外延生长介导的方法，即在 Pd-Cu 合金表面生长面心立方（fcc）Ru，而在体相中，fcc Ru 是热力学上不利的。在电替换作用下，Ru 与 Pd-Cu 合金之间发生反应，在外延生长过程中观察到从 Pd-Cu@Ru 核壳到蛋黄壳结构的形状转变。这种非常规晶体结构的成功包覆，关键取决于 fcc Ru 覆盖层与 PdCu3 合金衬底之间适中的晶格失配。此外，通过改变 Pd-Cu 衬底的晶格间距，可以选择性地生长出 fcc 和六方密堆积（hcp）Ru。本研究结果为控制金属纳米材料的晶体结构提供了一种新的合成途径。
