Oxidation of alkylsilane-based monolayers on gold.
The oxidation of alkylsilane monolayers on Au has been studied by X-ray photoelectron spectroscopy, reflection-absorption infrared spectroscopy, contact-angle measurements, and scanning tunneling microscopy. Exposure of the monolayers at 298 K to pure O(2) or H(2)O (>5 x 10(-5) Torr and >150 000 L) does not cause oxidation. Ambient atmosphere only causes oxidation if direct sight lines are maintained to the sample. Ozone exposure results in rapid monolayer oxidation. Oxidation initially occurs only at the Si atom, resulting in formation of a cross-linked siloxane monolayer that retains alkyl surface termination. Prolonged ozone exposures result in the oxidation and subsequent loss of the alkyl chain.
Owens
Thomas M
TM
Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109-1055, USA.
Ludwig
Bonnie J
BJ
Schneider
Kevin S
KS
Fosnacht
Daniel R
DR
Orr
Bradford G
BG
Holl
Mark M Banaszak
MM