Department of Chemistry, Brookhaven National Laboratory, Building 555, Upton, New York 11973, USA.
Nat Commun. 2013;4:2466. doi: 10.1038/ncomms3466.
Fabricating subnanometre-thick core-shell nanocatalysts is effective for obtaining high surface area of an active metal with tunable properties. The key to fully realize the potential of this approach is a reliable synthesis method to produce atomically ordered core-shell nanoparticles. Here we report new insights on eliminating lattice defects in core-shell syntheses and opportunities opened for achieving superior catalytic performance. Ordered structural transition from ruthenium hcp to platinum fcc stacking sequence at the core-shell interface is achieved via a green synthesis method, and is verified by X-ray diffraction and electron microscopic techniques coupled with density functional theory calculations. The single crystalline Ru cores with well-defined Pt bilayer shells resolve the dilemma in using a dissolution-prone metal, such as ruthenium, for alleviating the deactivating effect of carbon monoxide, opening the door for commercialization of low-temperature fuel cells that can use inexpensive reformates (H2 with CO impurity) as the fuel.
制备亚纳米厚核壳纳米催化剂对于获得具有可调性质的高表面积活性金属非常有效。充分发挥这种方法潜力的关键是一种可靠的合成方法，用于生产原子有序的核壳纳米粒子。在这里，我们报告了在核壳合成中消除晶格缺陷的新见解，以及实现卓越催化性能的机会。通过绿色合成方法实现了核壳界面处钌 hcp 到铂 fcc 堆积序列的有序结构转变，并通过 X 射线衍射和电子显微镜技术以及密度泛函理论计算得到了验证。具有明确 Pt 双层壳的单晶 Ru 核解决了使用易溶解金属（如钌）来缓解一氧化碳失活效应的难题，为使用廉价重整料（含 CO 杂质的 H2）作为燃料的低温燃料电池的商业化开辟了道路。
