Polymer-assisted crystallization of low-dimensional lead sulfide particles

PbS micro- and nanoparticles were synthesized by a simple precipitation reaction of lead nitrate with thioacetamide in hydrosoluble polymer water solutions. The effects of four water soluble polymers: polyacrylamide (PAM), polyvinyl alcohol (PVA), polyethylene glycol (PEG) and poly-N-vinyl pyrrolidone (PVP) on the PbS crystallites morphology and structural properties were investigated by scanning electron microscopy (SEM) and X-ray diffraction (XRD). It was found that for the PbS particles obtained in the PVA, PEG and PVP, the (200) diffraction peak of the nanocrystals becomes dominant. The highest texture in the [200] direction was observed for the crystallites obtained in the presence of PVP. Polydisperse PbS particles with cubic morphology and size ranging from 100nm to several microns are obtained in the case of PAM and PEG. Monodisperse cubic PbS crystallites with an average size of 200nm are formed in the presence of PVA and PVP.