Formation of one-dimensional electronic states along the step edges of CeO2(111).
Formation of one-dimensional electronic states along the step edges of CeO2(111)
N. Nilius, S.M. Kozlov, J.-F. Jerratsch, M. Baron, X. Shao, F. Viñes, S. Shaikhutdinov, K.M. Neyman, H.-J. Freund.
ACS Nano, 6 (2012) 1126.
Outstanding red-ox properties of cerium oxide attract worldwide attention to this material as a catalyst or a catalyst support. In the above mentioned paper we have shown that some properties of ceria surfaces may be altered by high-temperature annealing, which would induce formation of ceria nanoislands bordered by three different step types with different properties. The paper is devoted to determination of atomic structure of these steps and characterization of their electronic structure using scanning tunneling microscopy and spectroscopy experiments combined with computational methods based on density functional theory. The results of theoretical and experimental investigations nicely agreeing with each other reveal that properties of steps are strongly affected by dipole moments produced by missing O anions. This work paves the way for further theoretical and experimental studies on model ceria catalysts with well characterized nanostructure.