Speciation atlas of polyoxometalates in aqueous solution (Part II): Molybdenum browns.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 41171926.
- Also identified by DOI 10.1126/sciadv.aea1910 and PMC identifier 12577712.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
We present a validated, openly accessible workflow and spectral database charting the solution speciation of molybdenum browns. These redox-active polyoxometalates are central to catalysis and increasingly explored for bioinspired transformations and nanomedicine, making their solution behavior critical for both mechanistic understanding and practical use. Two archetypal Keplerate-type polyoxometalates, {Mo<sub>72</sub>V<sub>30</sub>} and {W<sub>72</sub>V<sub>30</sub>}, were investigated under 69 systematically varied aqueous conditions. Complementary <sup>51</sup>V/<sup>31</sup>P nuclear magnetic resonance, resonance Raman, electrospray ionization mass spectrometry, and ultraviolet-visible spectroscopy interrogate the effects of pH, buffer identity, temperature, and incubation time on Keplerate integrity. Substituting Mo with W changes redox potential and hard/soft metal balance, yielding distinct stability patterns: {Mo<sub>72</sub>V<sub>30</sub>} breaks into fragments under all tested conditions whereas {W<sub>72</sub>V<sub>30</sub>} remains intact in fresh solutions and retains structural integrity up to pH 4 after 24 hours. All raw spectra, processed data, and stepwise protocols are deposited in a FAIR (findable, accessible, interoperable, reusable) repository, providing an open resource to accelerate catalytic and biological applications of polyoxometalates.