Thermal decomposition of sulfur-containing organotin molecular precursors to produce phase-pure SnS

The present work reports a simple route to prepare tin(II) sulfide semiconductor nanometric particles by thermal decomposition in air of the easily prepared organotin sulfur-containing precursors R4Sn4S6 [R = Me, Bu-n and Ph]. Thermogravimetric (TG) analyses showed that Me and Bu-n derivatives decompose in a single sharp step at relatively low temperatures to produce the pure SnS phase, which was confirmed by powder X-ray diffraction (XRD). Temperature programmed decomposition-mass spectrometry (TPD/MS) experiments suggested that the decomposition occurs via reductive elimination steps involving the -R and -S groups. The ring structured R6Sn3S3 [R = Me, Bu-n, Bu-t and Ph] compounds were also studied. However, during thermal decomposition in nitrogen or air tin is partially lost to the gas phase due to sublimation, leaving Sn or SnO, with only traces of SnS.