Reactions of tetraethoxysilane vapor on polycrystalline titanium dioxide

Journal Article · Thu Jan 12 04:00:00 EST 1995 · Journal of Physical Chemistry; (United States)

DOI:https://doi.org/10.1021/j100002a042· OSTI ID:6868392

Jurgens, T A; Rogers, Jr, J W ^[1]

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1. Univ. of Washington, Seattle, WA (United States)

The reactions of tetraethyoxysilane (TEOS) vapor on dehydroxylated and water predosed polycrystalline TiO[sub 2] were studied by Fourier transform infrared spectroscopy (FTIR) and temperature-programmed desorption (TPD). Exposure at 300 K leads to dissociative adsorption producing a monoethoxysilyl ligand and surface ethoxide species. The ethoxide ligands react and desorb in the range 450-650 K as gas phase ethanol and ethylene, while the monoethoxysilyl ligand decomposes at approximately 650 K to gas phase ethanol and ethylene and surface bound SiO[sub 2]. Dissociation of TEOS on TiO[sub 2] is not affected by water predose; although, a greater amount of ethanol is produced in the gas phase at 550-650 K, and the SiO[sub 2] which is formed exhibits vibrational features characteristic of a hydroxylated species. TEOS chemistry on TiO[sub 2] was compared to the adsorption and reaction of ethanol on the same surface. Adsorption of ethanol at 300 K yielded surface ethoxide species which desorbed in two states as the parent alcohol and ethylene; desorption was also centered at 450 and 650 K. These results complement and supplement our previous study of TEOS on a TiO[sub 2](110) single crystal surface. 65 refs., 8 figs., 4 tabs.

• OSTI ID: 6868392
• Journal Information: Journal of Physical Chemistry; (United States), Journal Name: Journal of Physical Chemistry; (United States) Vol. 99:2; ISSN JPCHAX; ISSN 0022-3654
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400102 -- Chemical & Spectral Procedures
400201* -- Chemical & Physicochemical Properties
ADSORPTION
ALCOHOLS
CHALCOGENIDES
CHEMICAL REACTIONS
CRYSTALS
DATA
DESORPTION
DISSOCIATION
EMISSION SPECTROSCOPY
ETHANOL
EXPERIMENTAL DATA
FLUIDS
FOURIER TRANSFORM SPECTROMETERS
GASES
HYDRIDES
HYDROGEN COMPOUNDS
HYDROXY COMPOUNDS
INFORMATION
MEASURING INSTRUMENTS
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC SILICON COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
POLYCRYSTALS
SILANES
SILICON COMPOUNDS
SORPTION
SPECTROMETERS
SPECTROSCOPY
TITANIUM COMPOUNDS
TITANIUM OXIDES
TRANSITION ELEMENT COMPOUNDS
VAPORS