COLLOIDAL NANOCRYSTAL ENSEMBLES WITH NARROW LINEWIDTH BAND GAP PHOTOLUMINESCENCE AND METHODS OF SYNTHESIZING COLLOIDAL SEMICONDUCTOR NANOCRYSTALS

摘要

A method of synthesizing colloidal semiconductor nanocrystals involvescontacting a source of at least one semiconductor cation element (Group 11-14,morepreferably Group 12-14, more preferably 12 or 14, more preferably Cd, Zn, Hgor Pb,most preferably Cd) with a source of at least one Group 15, or 16 element inthepresence of a ligand forming compound containing a carboxylic acid moiety in areactionmedium comprising a solvent that is substantially noncoordinating with respectto the atleast one cation, the ligand forming compound and the source of at least onecationelement having a molar ratio of 1:1 or less. The cation element source ispreferablybonded to two low carbon acids. Some of the low carbon acids are substitutedwith theligand forming compound to produce a cation precursor that is more soluble inthenoncoordinating solvent. The method produces novel ensembles of colloidalsemiconductor nanocrystals that have narrow linewidth absorption and bandgapphotoluminescence spectra indicating that the colloidal semiconductornanocrystals are ofsubstantially a single size. The single size families are produced for CdSe,CdTe, CdS,CdSeTe, and CdP.