Relationships between the structure and the surface activity of nano-sized alumina in acid catalysis
- Univ. of Wisconsin, Milwaukee, WI (United States)
As shown in another communication to Symposium 5, nano-sized aluminas enriched in pentacoordinated aluminum (Al{sup V}) are obtained through the limited hydrolysis of aluminum alkoxides. Here the surface properties of these aluminas are investigated from the catalytic point of view. The goal is to obtain geometrical information on the Lewis acid sites. {sup 1}H{r_arrow}{sup 27}Al (cross-polarization) high resolution MAS NMR, using chemisorbed NH{sub 3} which acts as a {sup 1}H spin reservoir, allows the direct observation of surface Al involved in the catalytic site. The polarization transfer from these protons to surface Al is remarkably efficient because of the relatively short Al:N-H distance. It is observed that the main Lewis acid sites are located on distorted tetrahedral aluminum and pentacoordinated Al. These results are compared to low temperature infrared data of adsorbed CO.
- OSTI ID:
- 51669
- Report Number(s):
- CONF-940411-; ISBN 1-55899-246-4; TRN: IM9524%%134
- Resource Relation:
- Conference: Spring meeting of the Materials Research Society (MRS), San Francisco, CA (United States), 4-8 Apr 1994; Other Information: PBD: 1994; Related Information: Is Part Of Better ceramics through chemistry VI. Materials Research Society symposium proceedings Volume 346; Cheetham, A.K. [ed.] [Univ. of California, Santa Barbara, CA (United States)]; Brinker, C.J. [ed.] [Sandia National Labs., Albuquerque, NM (United States)]; Mecartney, M.L. [ed.] [Univ of California, Irvine, CA (United States)]; Sanchez, C. [ed.] [Univ. Pierre et Marie Curie, Paris (France)]; PB: 1069 p.
- Country of Publication:
- United States
- Language:
- English
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