title: Covalent attachment of organic monolayers to silicon carbide surfaces.
abstract: This work presents the first alkyl monolayers covalently bound on HF-treated silicon carbide surfaces (SiC) through thermal reaction with 1-alkenes. Treatment of SiC with diluted aqueous HF solutions removes the native oxide layer (SiO2) and provides a reactive hydroxyl-covered surface. Very hydrophobic methyl-terminated surfaces (water contact angle theta = 107 degrees ) are obtained on flat SiC, whereas attachment of omega-functionalized 1-alkenes also yields well-defined functionalized surfaces. Infrared reflection absorption spectroscopy, ellipsometry, and X-ray photoelectron spectroscopy measurements are used to characterize the monolayers and show their covalent attachment. The resulting surfaces are shown to be extremely stable under harsh acidic conditions (e.g., no change in theta after 4 h in 2 M HCl at 90 degrees C), while their stability in alkaline conditions (pH = 11, 60 degrees C) also supersedes that of analogous monolayers such as those on Au, Si, and SiO2. These results are very promising for applications involving functionalized silicon carbide.
authors.affiliation: Laboratory of Organic Chemistry, Wageningen University, Dreijenplein 8, Wageningen, The Netherlands.
authors.forename: Michel
authors.initials: M
authors.lastname: Rosso
authors.forename: Ahmed
authors.initials: A
authors.lastname: Arafat
authors.forename: Karin
authors.initials: K
authors.lastname: Schroën
authors.forename: Marcel
authors.initials: M
authors.lastname: Giesbers
authors.forename: Christopher S
authors.initials: CS
authors.lastname: Roper
authors.forename: Roya
authors.initials: R
authors.lastname: Maboudian
authors.forename: Han
authors.initials: H
authors.lastname: Zuilhof
mesh_terms: D000475:Alkenes / Q000737:chemistry; D000478:Alkylation; D017554:Carbon Compounds, Inorganic / Q000737:chemistry*; D017646:Organosilicon Compounds / Q000737:chemistry*; D017655:Silicon Compounds / Q000737:chemistry*; D013053:Spectrophotometry; D013499:Surface Properties; D014867:Water / Q000737:chemistry
chemical_list: D000475:Alkenes; D017554:Carbon Compounds, Inorganic; D017646:Organosilicon Compounds; D017655:Silicon Compounds; D014867:Water; C022088:silicon carbide