Small-angle X-ray scattering studies of emergent polyoxometalates in solution

Abstract

The characterization of polyoxometalates (POMs) structures in solutions is challenging although X-ray diffraction is widely used to solve the POMs’ crystalline structures. Here, we introduce small-angle X-ray scattering (SAXS) to explore the solutions of several emergent POMs mainly from Prof. Enbo Wang’s group. Direct evidence of their crystal structure retained in solution is obtained by fitting their SAXS data with appropriate crystal structure models, ensuring credibility of their applications for catalysis and magnetism. The capability of distinguishing dimer and monomer structures of {Ce₂₀W₁₀₀} in solution is of special interest, which is difficult for other characterization techniques.

Graphic abstract

Keywords:

• Polyoxometalates
• solution chemistry
• small-angle X-ray scattering
• model fitting
• dimerization

Acknowledgements

We are grateful to 12-ID-B of Advanced Photon Source and BL19U2 station of the Shanghai Synchrotron Radiation Facility for the access to the synchrotron-based SAXS. We are grateful to Prof. Enbo Wang, Prof. Ulrich Kortz, and Prof. Masooma Ibrahim for providing crystalline POM samples.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The work is supported by the National Natural Science Foundation of China [No. U1832220], [No. 51873067], and [No. 21961142018]; the National Key Research and Development Program of China [No. 2018YFB0704200]; the Natural Science Foundation of Guangdong Province [No. 2018A030313503].