Abstract

Bis(n-hexyl(methyl)dithiocarbamato)platinum(II) and bis(n-hexyl(methyl)dithiocarbamato)palladium(II) have been synthesised and characterised.

Both complexes have been used as precursors to grow thin films of PtS and PdS, respectively, on to GaAs substrates by the low pressure metal organic chemical vapour deposition (LP-MOCVD) method. The grown films were characterised by XRD, EDAX and SEM methods. These complexes are useful precursors for the growth of nanocrystals of PtS or PdS by thermolysis in trioctylphosphine oxide (TOPO). TOPO capped monodispersed nanoparticles of PtS (ca. 3 nm diameter) and PdS (ca. 5 nm diameter) have been prepared using the corresponding precursors. The PtS nanoparticles exhibit a strong excitonic peak at 360 nm in the absorption spectrum with the band edge at 410 nm. There is no visible excitonic peak in the absorption spectrum of the PdS nanoparticles with the band edge at 455 nm. The emission maxima of PtS (495 nm) and PdS (465 nm) are red shifted in relation to their band edges. XRD patterns showed both materials to exist in the tetragonal phase. The EDAX spectra show the presence of palladium and sulfur, and platinum and sulfur, with a strong peak for phosphorus due to TOPO.