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Updated: Jun 7, 2025
Atomic Layer Deposition of Vanadium Dioxide and a Temperature-dependent Optical Model
Published on: May 23, 2018
Vanadium Substitution Dictates H Atom Uptake at Lindqvist-type Polyoxotungstates
Dominic Shiels1,2, Zhou Lu1, Magda Pascual-Borràs2
1Department of Chemistry, University of Rochester, Rochester, New York 14627, United States.
Abstract:
Understanding how modification of molecular structures changes the thermochemistry of H atom uptake can provide design criteria for the formation of highly active catalysts for reductive transformations. Herein, we describe the effect of doping an atomically precise polyoxotungstate with vanadium on proton-coupled electron transfer (PCET) reactivity. The Lindqvist-type polyoxotungstate [W6O19]2- displays reversible redox chemistry, which was found to be unchanged in the presence of acid, indicating an inability to couple reduction with protonation. However, the incorporation of a single vanadium center into the structure significantly changes the reactivity, and the potential required for one-electron reduction of [VW5O19]3- was shown to vary with the strength of the acid added. Construction of a potential-pKa diagram allowed assessment of the thermodynamics of H atom uptake, indicating BDFE(O-H) ≈ 64 kcal/mol, while chemical synthesis of the reduced/protonated derivative (TBA)3[VW5O19H] was used to probe the position of protonation.
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