Structural and optical studies of silver sulfide nanoparticles from silver(I) dithiocarbamate complex: molecular structure of ethylphenyl dithiocarbamato silver(I)

We report the synthesis and crystal structure of ethylphenyl dithiocarbamato silver(I) complex. The compound crystallized as [Ag-4(EtphDTC)(4)] in which four Ag(I) ions and four molecules of ethylphenyl dithiocarbamato ligands constitute the metal cluster in the asymmetric unit. Each ethylphenyl dithiocarbamato ligand in the cluster is bonded to three Ag(I) ions through the sulfur atoms with one sulfur covalently bonded while the other sulfur atoms act as two electrons-three centres within the metal cluster. Each Ag(I) ion is linked to three Ag(I) ions through Ag-Ag metallic bond distance of 2.9115(3) angstrom and 3.0376(4) angstrom. The complex was thermolyzed at 120, 180 and 220 degrees C as single source precursor to prepare silver sulfide nanoparticles. Powder XRD patterns confirmed the as-prepared silver sulfide nanoparticles as acanthite Ag1.93S irrespective of the thermolysis temperature. TEM images of the silver sulfide nanoparticles showed particle of 2.99 nm for AgS1 nanoparticles obtained at 120 degrees C, 6.71 nm for AgS2 obtained at 180 degrees C and HRTEM image of AgS3 obtained at 220 degrees C showed average particle size of 32.90 nm. The results showed that the particle sizes of the as-prepared silver sulfide nanoparticles increases with thermolysis temperature. The as-prepared silver sulfide nanoparticles have spherical shapes irrespective of thermolysis temperature.