Olefin metathesis reaction on GaN (0001) surfaces
Date of this Version3-1-2011
Applied Surface Science Volume 257, Issue 10, 1 March 2011, Pages 4625–4632
Proof-of-concept reactions were performed on GaN (0001) surfaces to demonstrate surface termination with desired chemical groups using an olefin cross-metathesis reaction. To prepare the GaN surfaces for olefin metathesis, the surfaces were hydrogen terminated with hydrogen plasma, chlorine terminated with phosphorous pentachloride, and then terminated with an alkene group via a Grignard reaction. The olefin metathesis reaction then bound 7-bromo-1-heptene. The modified surfaces were characterized by X-ray photoelectron spectroscopy (XPS), atomic force microscopy, and water contact angle measurements following each step in the reaction scheme. The XPS data was used to qualitatively identify surface chemical species and to quantitatively determine molecular surface coverage. The bromine atom in 7-bromo-1-heptene served as a heteroatom for identification with XPS. The reaction scheme resulted in GaN substrates with a surface coverage of 0.10 monolayers and excellent stability towards oxidation when exposed to oxygen plasma. (C) 2010 Elsevier B.V. All rights reserved.
Nanoscience and Nanotechnology