Lee Si Woo, Luna Mauricio Lopez, Berdunov Nikolay, Wan Weiming, Kunze Sebastian, Shaikhutdinov Shamil, Cuenya Beatriz Roldan
Department of Interface Science, Fritz Haber Institute of the Max Planck Society, 14195, Berlin, Germany.
Nat Commun. 2023 Aug 2;14(1):4649. doi: 10.1038/s41467-023-40361-3.
Gallium-containing alloys have recently been reported to hydrogenate CO to methanol at ambient pressures. However, a full understanding of the Ga-promoted catalysts is still missing due to the lack of information about the surface structures formed under reaction conditions. Here, we employed near ambient pressure scanning tunneling microscopy and x-ray photoelectron spectroscopy to monitor the evolution of well-defined Cu-Ga surfaces during CO hydrogenation. We show the formation of two-dimensional Ga(III) oxide islands embedded into the Cu surface in the reaction atmosphere. The islands are a few atomic layers in thickness and considerably differ from bulk GaO polymorphs. Such a complex structure, which could not be determined with conventional characterization methods on powder catalysts, should be used for elucidating the reaction mechanism on the Ga-promoted metal catalysts.
最近有报道称，含镓合金在常压下可将一氧化碳氢化为甲醇。然而，由于缺乏关于反应条件下形成的表面结构的信息，目前仍未完全了解镓促进型催化剂。在此，我们利用近常压扫描隧道显微镜和X射线光电子能谱来监测一氧化碳加氢过程中定义明确的铜 - 镓表面的演变。我们展示了在反应气氛中嵌入铜表面的二维氧化镓（III）岛的形成。这些岛的厚度为几个原子层，与块状氧化镓多晶型物有很大不同。这种复杂结构无法用粉末催化剂的传统表征方法确定，应用于阐明镓促进型金属催化剂的反应机理。
