INTRAZEOLITE NONSTOICHIOMETRIC TUNGSTEN-OXIDES N[WO3-X]-NA56Y(0-LESS-THAN-N-LESS-THAN-OR-EQUAL-TO-32, 0-LESS-THAN-OR-EQUAL-TO-X-LESS-THAN-OR-EQUAL-TO-1)

Date

1992-11-01

Author

OZIN, GA
PROKOPOWICZ, RA
Özkar, Saim

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The photooxidation of alpha-cage encapsulated n[W(CO)6]-Na56Y, where 0 hv n[WO3]-Na56Y + 6nCO2 Following photooxidation, half of the alpha-cage void volume in the Na56Y host is freed so that subsequent precursor (saturation level) impregnations/photooxidations can be carried out in a stepwise fashion, proceeding as n = 16, 24, 28, 30, ..., 32 per unit cell. Thermal vacuum treatment of these materials proceeds in two well-defined steps around 300 and 400-degrees-C to yield encapsulated n[WO3-x]-Na56Y materials having x = 0.5 and 1, respectively. This reduction process is reversible by heating in an O2 atmosphere at 300-degrees-C. The entire redox process can be summarized according to the reaction stoichiometry

Subject Keywords

Colloid and Surface Chemistry, Biochemistry, General Chemistry, Catalysis

URI

https://hdl.handle.net/11511/69995

Journal

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY

DOI

https://doi.org/10.1021/ja00049a028

Collections

Department of Chemistry, Article

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Citation Formats

G. OZIN, R. PROKOPOWICZ, and S. Özkar, “INTRAZEOLITE NONSTOICHIOMETRIC TUNGSTEN-OXIDES N[WO3-X]-NA56Y(0-LESS-THAN-N-LESS-THAN-OR-EQUAL-TO-32, 0-LESS-THAN-OR-EQUAL-TO-X-LESS-THAN-OR-EQUAL-TO-1),” JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, pp. 8953–8963, 1992, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/69995.