†State Key Laboratory of Catalysis, iChEM, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P.R. China.
‡State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, Xiamen University, Xiamen 361005, P.R. China.
Nano Lett. 2015 May 13;15(5):3616-23. doi: 10.1021/acs.nanolett.5b01205. Epub 2015 Apr 23.
In heterogeneous catalysis molecule-metal interaction is often modulated through structural modifications at the surface or under the surface of the metal catalyst. Here, we suggest an alternative way toward this modulation by placing a two-dimensional (2D) cover on the metal surface. As an illustration, CO adsorption on Pt(111) surface has been studied under 2D hexagonal boron nitride (h-BN) overlayer. Dynamic imaging data from surface electron microscopy and in situ surface spectroscopic results under near ambient pressure conditions confirm that CO molecules readily intercalate monolayer h-BN sheets on Pt(111) in CO atmosphere but desorb from the h-BN/Pt(111) interface even around room temperature in ultrahigh vacuum. The interaction of CO with Pt has been strongly weakened due to the confinement effect of the h-BN cover, and consequently, CO oxidation at the h-BN/Pt(111) interface was enhanced thanks to the alleviated CO poisoning effect.
在多相催化中，通过金属催化剂表面或表面下的结构修饰来调节分子-金属相互作用。在这里，我们通过在金属表面覆盖二维（2D）覆盖层来提出一种替代的调制方法。作为说明，在二维六方氮化硼（h-BN）覆盖层下研究了 CO 在 Pt(111)表面上的吸附。在接近环境压力条件下进行的表面电子显微镜动态成像数据和原位表面光谱结果证实，CO 分子在 CO 气氛中很容易插入 Pt(111)上的单层 h-BN 片，但即使在超高真空的室温下也会从 h-BN/Pt(111)界面上解吸。由于 h-BN 覆盖层的限制作用，CO 与 Pt 的相互作用大大减弱，因此，由于 CO 中毒效应的缓解，h-BN/Pt(111)界面上的 CO 氧化得到增强。
