Facile preparation of rare-earth semiconductor nanocrystals and tuning of their dimensionalities

EuS and Gd₂O₂S nanocrystals with narrow size distribution are synthesized in high yields by the thermal decomposition of Eu(oleate)₃ or Gd(oleate)₃ in oleylamine using CS₂ as the sulfur source. The dimensionalities of these nanocrystals can be facilely tuned by the addition of 1-dodecanethiol. The morphologies and crystal structures of EuS and Gd₂O₂S nanocrystals are characterized by TEM and XRD. The magnetic properties of the obtained nanocrystals are also investigated. The experimental results illustrate that CS₂ is an effective sulfur source for the preparation of metal sulfide and lanthanide oxysulfide semiconductor nanocrystals.