Abstract The catalytic CO oxidation reaction on stepped Rh surfaces in the 10 −6 mbar pressure range was studied in situ on individual μm-sized high-Miller-index domains of a polycrystalline Rh foil and on nm-sized facets of a Rh tip, employing photoemission electron microscopy (PEEM) and field-ion/field-emission microscopy (FIM/FEM), respectively. Such approach permits a direct comparison of the reaction kinetics for crystallographically different regions under identical reaction conditions. The catalytic activity of the different Rh surfaces, particularly their tolerance towards poisoning by CO, was found to be strongly dependent on the density of steps and defects, as well as on the size (µm vs. nm) of the respective catalytically active surface. Graphic Abstract

中文翻译：

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阶梯式 Rh 表面上的 CO 氧化：微米级与纳米级

摘要 在 10 -6 mbar 压力范围内，在多晶 Rh 箔的单个 μm 尺寸高米勒指数域和 Rh 尖端的 nm 尺寸小面上原位研究了阶梯 Rh 表面上的催化 CO 氧化反应，采用分别是光发射电子显微镜 (PEEM) 和场离子/场发射显微镜 (FIM/FEM)。这种方法允许在相同反应条件下直接比较晶体学不同区域的反应动力学。发现不同 Rh 表面的催化活性，特别是它们对 CO 中毒的耐受性，强烈依赖于台阶和缺陷的密度，以及相应催化活性表面的尺寸（μm 与 nm）。图形摘要