Manuscript Accepted by Langumir Co-Authored by Lauren Benz
Thursday, June 14, 2012
Professor Lauren Benz, PhD, recently had a manuscript accepted by Langmuir entitled "The Interaction of Petroleum-Relevant Organosulfur Compounds with TiO2(110)." The manuscript was coauthored by USD students Aileen Park, Jenelle Renee Corey, Michelle Mezher and Victoria Park.
The interaction of two sets of structurally related molecules, thiophenol / thioanisole, and thiophene / tetrahydrothiophene, with vacuum-annealed and ion-bombarded TiO2(110) surfaces has been studied using a combination of temperature programmed reaction spectroscopy (TPRS) and X-ray photoelectron spectroscopy (XPS). All thioethers studied were observed to adsorb and desorb from both surfaces without producing reaction products, while thiophenol, the only species studied containing a S-H bond, reacted with both surfaces. Approximately 25% of surface bound thiophenol decomposed over the vacuum-annealed surface. On the bombarded surface, thiophenol both decomposed into surface-bound CxHy / S fragments, and reacted to form benzene, which desorbed from the surface at 400 K. We propose that phenylthiolate formation on the bombarded surface leads to the observed production of benzene. These results highlight the importance of defects in the reactivity of titania, and lay the foundation for the study of larger, refractory sulfur compounds present in fuel.