Tuning Particle Sizes of Alkaline-Earth Chalcogenides

Electron micrographs
Unit cells & electron micrographs of alkaline-earth chalcogenide (AeCh) nanocrystals (top left). Evolution of XRD peak width and particle size (lower left). 77Se ssNMR of AeSe nanocrystals (right). 
Scientific Achievement

Alkaline-earth chalcogenide nanocrystals (AeChn = Ae = Ca, Sr, Ba, Ch = S, Se, n = 1, 2, 3) from earth-abundant and biocompatible elements of metal carboxylates and CS2 or selenourea.

Significance and Impact
  • Versatile optical materials when doped with rare earths.
  • Alkaline-earth-based multinaries may now be accessed in the region of the synthetic space where AeCh and a second binary phase nucleate at similar rates.
Research Details
  • Achieved control of particle size over a wide range using a mixture of readily available metal-carboxylate precursors.
  • 77Se ssNMR confirms phase purity of AeSen (n = 1, 2, 3).
  • Bridging carboxylates and amines terminate nanocrystal surface (FTIR and NMR spectroscopy).
  • Electronic structure calculations of BaSe2 and BaSe3.

Alison N. Roth, Yunhua Chen, Marquix A. S. Adamson, Eunbyeol Gi, Molly Wagner, Aaron J. Rossini, and Javier Vela, ACS Nano 2022 16(8), 12024-12035, DOI: 10.1021/acsnano.2c02116