Defect Structure of Nonstoichiometric CeO{sub 2}(111) Surfaces Studied by Scanning Tunneling Microscopy

Journal Article · Sat Nov 01 00:00:00 EST 1997 · Physical Review Letters

DOI:https://doi.org/10.1103/PhysRevLett.79.4222· OSTI ID:553138

Noerenberg, H; Briggs, G A ^[1]

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1. University of Oxford, Department of Materials, Parks Road, Oxford OX1 3PH (United Kingdom)

The surface structure of nonstoichiometric CeO{sub 2}( 111) has been studied by scanning tunneling microscopy (STM). By using extremely small tunneling currents it was possible to obtain the first ever reported atomically resolved images of this oxide. STM imaging was possible at a sample bias voltage between {minus}2 and {minus}3.5 V . Comparing this with the band structure of ceria we claim that the main contribution to the image contrast results from oxygen in the topmost layer. The dominant defect type on the surface at RT is of triangular shape and contains three oxygen vacancies. Elevated temperature STM at a substrate temperature of 500{degree}C revealed an alignment of oxygen vacancies on the surface. The defect shapes are in qualitative agreement with previous energy calculations. {copyright} {ital 1997} {ital The American Physical Society}

• OSTI ID: 553138
• Journal Information: Physical Review Letters, Vol. 79, Issue 21; Other Information: PBD: Nov 1997
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CERIUM OXIDES
CRYSTAL DEFECTS
STOICHIOMETRY
IMAGES
VACANCIES
TEMPERATURE DEPENDENCE