Synthesis of multi-podal CdS nanostructures using heterocyclic dithiocarbamato complexes as precursors

Abstract

Bis(dipiperidinyldithiocarbamato)cadmium(II) (1) and bis(ditetrahydroquinolinyldithio-carbamato)cadmium(II) (2) were used as precursors for the synthesis of oleylamine (OA), decylamine (DA) and dodecylamine (DDA) capped CdS nanoparticles. The optical properties of these particles have been studied. The absorption spectra for the amine capped CdS particles are blue shifted in relation to the bulk material. The corresponding photoluminescence spectra show a narrow band edge emission. High quality crystalline CdS particles of different shapes, ranging from short nanorods and elongated nanorods (rods, bipods, tripods and tetrapods) to nanocubes were obtained when the reaction temperature was varied between 180 and 270°C. A decrease in the length of the rods and bipodal nanoparticles was observed with an increase in the length of the chain of the amine (capping agent) used. The p-XRD patterns revealed the hexagonal phase of CdS to be dominant in all the samples. Infra-red studies suggest that the mode of bonding of the amines (oleylamine, decylamine and dodecylamine) on the CdS nanoparticle surfaces is through electron donation from the nitrogen atoms.