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05:47
Preparation of Polyoxometalate-based Photo-responsive Membranes for the Photo-activation of Manganese Oxide Catalysts
Published on: August 7, 2018
Heteroatom-controlled kinetics of switchable polyoxometalate frameworks.
Johannes Thiel1, Chris Ritchie, Carsten Streb
1WestCHEM Department of Chemistry, Joseph Black Building, University of Glasgow, University Avenue, Glasgow G12 8QQ, UK.
Journal of the American Chemical Society
|March 12, 2009
Summary
Framework materials exhibit heteroatom-controlled redox reactions. The Ge-templated framework shows fast reduction and slow reoxidation, while the Si-templated framework displays the opposite trend.
Area of Science:
- Inorganic Chemistry
- Materials Science
- Solid-State Chemistry
Background:
- Framework materials with the general formula [W(72)Mn(II/III)(12)O(268)X(7)](52-/40-) are investigated.
- These materials are known to undergo redox reactions.
Purpose of the Study:
- To investigate the heteroatom (X)-controlled reversible redox reactions in these framework materials.
- To understand the kinetics of reduction and reoxidation processes in Ge-templated versus Si-templated frameworks.
Main Methods:
- The study employs optical, spectroscopic, and crystallographic techniques.
- These methods are used to monitor the solid-state (SC-SC) redox reactions.
Main Results:
- Heteroatom (X) substitution controls the reversibility of SC-SC redox reactions.
- Ge-templated frameworks exhibit fast reduction and slow reoxidation.
- Si-templated frameworks show the opposite kinetic trend: slow reduction and fast reoxidation.
Conclusions:
- The kinetics of redox reactions in these framework materials are tunable via templating atoms (Ge vs. Si) and heteroatom substitution.
- The distinct kinetic behaviors offer opportunities for designing materials with specific redox properties.
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