Raman characterization of CdTe/CdS-"core-shell"-clusters in colloids and films

We present the Raman spectroscopic characterization of thermally sintered C dTe/CdS-colloids in thin films. From the spectral data one can conclude tha t the thermal sintering of the CdTe/CdS-films between 100 degrees C and 200 degrees C initiates the CdTe cluster growth. Sintering temperatures of 300 -400 degrees C lead to a release of the Tributylphosyhin- (TBP) capping lig ands and to the formation of bare CdS- and CdTe nanocrystals. Above 400 deg rees C, the CdTe part of the nanostructures sublimates, leaving behind near ly pure CdS nanocrystallites. (C) 2000 Elsevier Science B.V. All rights res erved.