Morphological stability of oxygen- and nitrogen-covered Ru(11(2)over-bar1)

作者：Shen Quantong^*; Chen Wenhua; Wang Hao; Bartynski Robert A

来源：Journal of Chemical Physics, 2013, 139(8): 084707.

DOI：10.1063/1.4819130

Morphological stability of the atomically rough Ru(11 (2) over tilde1) surface upon annealing in NO2, O-2, and NH3 at elevated temperatures has been studied using scanning tunneling microscopy (STM), low energy electron diffraction (LEED), and Auger electron spectroscopy. The surface becomes fully faceted and covered by oxygen after annealing at T >= 600 K in NO2 (10(-8) Torr) or O-2 (10(-6) Torr). The LEED and STM studies reveal that the faceted surface consists of nanoscale ridges, exposing four facets (10 (1) over bar1), (01 (1) over bar1), (10 (1) over bar0), and (01 (1) over bar0) on the ridges, and the ridge size grows as the annealing temperature increases. Details of the facet structures and reconstructions have been observed. However, no evidence is found for faceting of Ru(11 (2) over bar1) to occur upon annealing in NH3. Our findings should be important for development of Ru-based catalysts under oxygen-rich conditions.

• 出版日期2013-8-28
• 单位rutgers