The anion-binding polyanion: a molecular cobalt vanadium oxide with anion-sensitive visual response
Andrey Seliverstov1, Johannes Forster, Magdalena Heiland
1Ulm University, Institute of Inorganic Chemistry I, Albert-Einstein-Allee 11, 89081 Ulm, Germany. carsten.streb@uni-ulm.de.
Chemical Communications (Cambridge, England)
|June 10, 2014
Summary
A novel anionic cobalt vanadium oxide cluster acts as a selective anion sensor. This molecular sensor exhibits reversible anion binding, enabling ratiometric optical detection of various anions even at high temperatures.
Area of Science:
- Inorganic Chemistry
- Materials Science
- Supramolecular Chemistry
Background:
- Development of molecular sensors for anion detection is crucial in various chemical and biological applications.
- Anion-dependent dynamic solution equilibria offer opportunities for designing responsive molecular systems.
- Challenges remain in achieving selectivity and stability under harsh conditions for anion sensing.
Purpose of the Study:
- To report the synthesis and characterization of an anionic molecular cobalt vanadium oxide cluster.
- To investigate the cluster's capability as a selective anion binding site.
- To demonstrate in situ ratiometric optical detection of anions using the cluster.
Main Methods:
- Synthesis of the anionic molecular cobalt vanadium oxide cluster, (n-Bu4N)3[Co(AcO)V4O12].
- Investigation of anion-dependent dynamic solution equilibria controlling cluster formation.
- Spectroscopic analysis (UV-Vis, etc.) to monitor reversible anion binding and spectral changes.
- In situ ratiometric optical detection experiments under varying conditions, including elevated temperatures (90 °C).
Main Results:
- The anionic cobalt vanadium oxide cluster demonstrates reversible anion binding in solution.
- Anion binding induces significant spectral changes, enabling ratiometric optical detection.
- The sensor operates effectively even at 90 °C, indicating thermal stability.
- Comparative studies reveal distinct spectral responses for different anion types (carboxylates, weakly coordinating anions, halides), demonstrating selectivity.
Conclusions:
- The (n-Bu4N)3[Co(AcO)V4O12] cluster serves as an effective anion binding site.
- The dynamic equilibrium and reversible binding allow for sensitive and selective anion detection.
- This molecular sensor shows promise for in situ anion concentration monitoring under demanding conditions.
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