A Library of Selenourea Precursors to PbSe Nanocrystals with Size Distributions near the Homogeneous Limit

J Am Chem Soc. 2017 Feb 15;139(6):2296-2305. doi: 10.1021/jacs.6b11021. Epub 2017 Feb 6.


We report a tunable library of N,N,N'-trisubstituted selenourea precursors and their reaction with lead oleate at 60-150 °C to form carboxylate-terminated PbSe nanocrystals in quantitative yields. Single exponential conversion kinetics can be tailored over 4 orders of magnitude by adjusting the selenourea structure. The wide range of conversion reactivity allows the extent of nucleation ([nanocrystal] = 4.6-56.7 μM) and the size following complete precursor conversion (d = 1.7-6.6 nm) to be controlled. Narrow size distributions (σ = 0.5-2%) are obtained whose spectral line widths are dominated (73-83%) by the intrinsic single particle spectral broadening, as observed using spectral hole burning measurements. The intrinsic broadening decreases with increasing size (fwhm = 320-65 meV, d = 1.6-4.4 nm) that derives from exciton fine structure and exciton-phonon coupling rather than broadening caused by the size distribution.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Lead / chemistry*
  • Molecular Structure
  • Nanoparticles / chemistry*
  • Organoselenium Compounds / chemistry*
  • Particle Size
  • Selenium Compounds / chemistry*
  • Surface Properties
  • Urea / analogs & derivatives*
  • Urea / chemistry


  • Organoselenium Compounds
  • Selenium Compounds
  • selenourea
  • lead selenide
  • Lead
  • Urea