COLL 435 |
| Sangyun Lim1, Dragos Ciuparu2, Yuan Chen2, Lisa Pfefferle2, and Gary Haller1. (1) Chemical Engineering, Yale University, P. O. 06520-8286, New Haven, CT 06520-8286, (2) Department of Chemical Engineering, Yale University, 9 Hillhouse Ave. ML310, New Haven, CT 06520-8286 |
| We demonstrate that Co-MCM-41 can be used to control the cluster size of cobalt metal in the pores, which will be potentially useful catalyst design for many catalytic applications. From TPR, the initiation of reduction and the complete reduction of Co2+ are linearly related to the pore size of Co-MCM-41, which is likely due to the radius of curvature effect of each pore size. The Co-Co coordination numbers obtained from EXAFS are increased as the pore size increases when samples are partially reduced. The size of this metal is extremely small (under 1 nm) that may still be anchored on the silica surface. After TPR, the coordination number patterns are opposite to the partially reduced sample because of the relatively free migration of Co on the pore wall surface without any confinement. |
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Symposium in Memory of Arthur W. Adamson
2:00 PM-5:40 PM, Wednesday, March 31, 2004 Marriott -- Orange County 4, Oral
Division of Colloid and Surface Chemistry |