Six new complexes of Zn(II), Cd(II) and Hg(II) with sulphur containing ligand, tetraethylthiuram disulphide in 2:2 and 1:4 ratio have been synthesized. The resulting complexes have been characterized on the basis of molar conductance measurement, elemental analyses, FT-IR, 1 H-NMR, and FAB/ESI-mass studies. The complexes were used as a single-source precursor for the synthesis of ZnS/CdS/HgS nanoparticles by their thermal decomposition in the presence of different surfactants. The precursor:surfactant ratio and temperature play an important role in determining the size of the nanoparticles. The size and morphology of nanoparticles have been ascertained by ultra violet-visible spectroscopy, X-ray diffraction measurements and transmission electron microscopy. Schiff bases, complexes and nanoparticles were tested for antibacterial activity and minimum inhibitory concentration values against Escherichia coli. The complexes were found more potent than the corresponding Schiff bases and nanoparticles.