Biosynthesis of CdS nanoparticles: An improved green and rapid procedure

A low-cost green and reproducible microbes (Lactobacillus sp. and Sachharomyces cerevisiae) mediated biosynthesis of CdS nanoparticles is reported. The synthesis is performed akin to room temperature in the laboratory ambience. X-ray and transmission electron microscopy analyses are performed to ascertain the formation of CdS nanoparticles. Individual nanoparticles as well as a few aggregate having the size of 2.5-5.5nm are found. UV-vis spectroscopy study revealed the surface plasmon resonance at 393 and 369nm respectively for Lactobacillus and yeast assisted synthesis of CdS nanoparticles. The absorbance spectra were used to estimate the values of optical band gap and particle size of CdS nanoparticles. A possible involved mechanism for the biosynthesis of CdS nanoparticles has also been proposed.