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Title: Oxygen-atom vacancy formation and reactivity in polyoxovanadate clusters
Reducible metal oxides (RMOs) are widely used materials in heterogeneous catalysis due to their ability to facilitate the conversion of energy-poor substrates to energy-rich chemical fuels and feedstocks. Theoretical investigations have modeled the role of RMOs in catalysis and found they traditionally follow a mechanism in which the generation of oxygen-atom vacancies is crucial for the high activity of these solid supports. However, limited spectroscopic techniques for in situ analysis renders the identification of the reactivity of individual oxygen-atom vacancies on RMOs challenging. These obstacles can be circumvented through the use of homogeneous complexes as molecular models for metal oxides, such as polyoxometalates. Summarized herein, a sub-class of polyoxometalates, polyoxovanadate–alkoxide clusters, ([V 6 O 7 (OR) 12 ] n ; R = CH 3 , C 2 H 5 ; n = 2−, 1−, 0), are explored as homogeneous molecular models for bulk vanadium oxide. A series of synthetic strategies have been employed to access oxygen-deficient vanadium oxide assemblies, including addition of V(Mes) 3 (thf), tertiary phosphanes, and organic acids to plenary Lindqvist motifs. We further detail investigations surrounding the ability of these oxygen-deficient sites to mediate reductive transformations such as O 2 and NO x 1− ( x = 2, 3) activation.  more » « less
Award ID(s):
1653195
NSF-PAR ID:
10249411
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Chemical Communications
Volume:
56
Issue:
88
ISSN:
1359-7345
Page Range / eLocation ID:
13477 to 13490
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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