Abstract's Details

Spectroscopic Investigation of Trimethyl Gallium Reactions on Silica and HZSM-5
Abstract ID	MAT-06
Presenter	Samuel Fleischman
Presentation Type	Poster
Full Author List	Z. Taha (2), S. Fleischman (1), E. Deguns (1), S. Chattopadhyay (2), S. L. Scott (1,2)
Affiliations	(1) Dept. of Chemistry & Biochemistry, UCSB (2) Dept. of Chemical Engineering, UCSB
Category	Materials Science
Abstract	Gallium dispersed on ZSM-5 catalyzes the dehydro-aromatization of alkanes and the selective reduction of nitrogen oxides by hydrocarbons. Trimethyl gallium has been used to make a uniform dispersion of gallium on both ZSM-5 and silica, in order to facilitate study of the structure of the active sites. Cryogenic EXAFS spectra, corroborated by DFT calculations, indicate dimethylgallium sites form oxygen-bridged dimers in ZSM-5 as well as on a silica surface pretreated at 500 ^oC. This finding has implications for proposed mechanisms of C-H activation, since earlier models assumed that gallium sites were isolated.
Footnotes
Funding Acknowledgement	This work was funded by the U.S. Department of Energy, Basic Sciences, Catalysis Science Grant no. DE-FG02-03ER15467 and the National Science Foundation under the PIRE-ECCI program grant no. OISE-0530268. Much of this research was carried out at the Stanford Synchotron Radiation Laboratory, a national user facility operated by Stanford University on behalf of the U.S. Department of Energy, Office of Basic Energy Sciences.