Structural Dynamics of the Active Re10 Cluster

A phenol synthesis by one-path benzene conversion of 5.8% proceeded on the Re10 cluster/HZSM-5 (19) catalyst in the steady-state reaction, but only the inactive 

Molecular oxygen was the active oxidant for the phenol synthesis and the maximum phenol selectivity (93.9%) was achieved on the N-interstitial Re cluster supported on HZSM-5. Molecular oxygen was activated in the space between the two Re6 octahedral cores of the Re10 cluster and benzene concertedly reacted on the activated 02 with the very low activation energy of 24 kj mol-1. The pore size of HZSM-5 is 5.5 A, which is similar to the size of the Re6-octahedral cluster framework, 

The dynamic XAFS study of the catalytically active structures under the reaction conditions should enable us to further develop novel catalysts for direct phenol synthesis from benzene and the efficient activation of molecular oxygen. 

10 Tada, M. and Iwasawa, Y. (2005) Annual Review of Materials Research, 35, 397-426. 

12 Iwasawa, Y. (1986) Tailored Metal Catalysts, Reidel, Dordrecht. 

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