Kinetics of the Reaction of Adsorbed Hexamethyldisilane on C/Pt(111) with D Atoms: Si−Si Bond Breaking

Autor:	Jürgen Küppers, and Th. Zecho, Stefan Wehner
Rok vydání:	2001
Předmět:	Thermal desorption spectroscopy Trimethylsilane Photochemistry Surfaces Coatings and Films Chemical kinetics chemistry.chemical_compound Adsorption chemistry Desorption Monolayer Materials Chemistry Molecule Physical and Theoretical Chemistry Hexamethyldisilane
Zdroj:	The Journal of Physical Chemistry B. 105:1799-1804
ISSN:	1520-5207 1520-6106
Popis:	The adsorption of hexamethyldisilane (HMDS) and trimethylsilane (H-TMS) on graphite monolayers on Pt(111) surfaces was studied with thermal desorption spectroscopy, and the kinetics of reactions of gaseous D atoms with adsorbed H-TMS and HMDS was investigated with reaction product detection techniques. HMDS and H-TMS adsorb and desorb molecularly in the mono- and multilayer regimes. Zero-order desorption indicates that in either regime the molecules tend to agglomerate in islands. Reaction of D atoms with adsorbed HMDS leads via insertion of D into the Si−Si bond to D-TMS products, either adsorbed or as gaseous species, depending on the substrate temperature. D impact-induced abstraction of H from the methyl groups and of methyl from HMDS is much less efficient than D insertion into the Si−Si bond, in accordance with the energetics involved. The reaction kinetics is compatible with an Eley−Rideal mechanism, and a reaction cross-section of σ = 0.4 A2 was obtained. Adsorbed H-TMS does not react with D.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::4d89ebb2154abd3df99a0ecb8ae7969f https://doi.org/10.1021/jp002481e Zobrazit plný text záznamu