Synthesis of CdSe nanoparticles using various organometallic cadmium precursors

Investigations into replacing Me₂Cd as a common precursor for the synthesis of CdSe nanoparticles by pyrolysis in a hot coordinating solvent have proven that more stable, less volatile or even crystalline organometallic cadmium compounds can be used instead of Me₂Cd. Dineopentylcadmium, bis(3-diethylaminopropyl)cadmium and (2,2′-bipyridine)dimethylcadmium have been used successfully as cadmium sources for the preparation of tri-n-octylphosphine oxide (TOPO)-capped CdSe nanoparticles. The resulting nanocrystallites have been characterized by UV-VIS and IR spectroscopy, photoluminescence spectroscopy (PL), mass spectrometry and transmission electron microscopy (TEM). They consist of separated, well defined spherical particles and show a small size distribution as well as a characterisitic blue shift due to quantum confinement in their optical spectra. The replacement of Me₂Cd by less dangerous organometallic precursors thus results in nanocrystallites that show no reduction in quality when compared to the standard method.