Atomic Scale Analysis of Ultrathin SiO2 Films Prepared on TiO2(100) Surfaces.
J PHYS CHEM C
20189 - 20194.
Rutile titanium dioxide (TiO2) (100) surfaces covered by silicon oxide (SiO2) ultrathin films were examined by X-ray photoelectron spectroscopy (XPS), low energy electron diffraction (LEED), and frequency modulation atomic force microscopy (FM-AFM) techniques. The SiO2 films were fabricated on TiO2 crystals by annealing in a quartz case which was used as a SiO2 source. The amount of Si increased with annealing time, and a (3 x 4) LEED pattern was observed on surfaces with the XPS peak intensity ratio of Si 2p to O 1s of TiO2 larger than 0.023. FM-AFM observation in pure water showed that the (3 x 4) surface consists of atomically flat terraces. Within the terraces, rows which extend in the  direction were observed. Every fourth row appeared brighter, consistent with the x4 periodicity in the  direction observed in LEED. Models where rutile SiO2 units are accumulated on the TiO2(100) surface via rutile Ti1-xSixO2 units are consistent with the results.
|Title:||Atomic Scale Analysis of Ultrathin SiO2 Films Prepared on TiO2(100) Surfaces|
|Keywords:||MIXED OXIDES, TITANIA-SILICA, SI, TI, EPOXIDATION, STISHOVITE, TIO2/SIO2, DIOXIDE, FILMS, WATER|
|UCL classification:||UCL > School of BEAMS > Faculty of Maths and Physical Sciences > Chemistry|
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