Morphology and size control of lead sulphide nanoparticles produced using methanolic lead acetate trihydrate-thiourea complex via different precipitation techniques

In this study, lead sulphide (PbS) particles were synthesized from methanolic lead acetate-thiourea (PbAc-TU) complex via various precipitation techniques based on the decomposition of methanolic PbAc-TU complex. The influence of these techniques on the morphology, size and physical properties of PbS particles was studied in details. In general, scanning electron microscopy of the PbS particles produced by conventional chemical bath deposition, sonochemical bath deposition and microwave-assisted chemical bath deposition revealed that they were nanostructured with different size and shape. X-ray diffraction confirmed their high purity, while X-ray photoelectron spectroscopy (XPS) showed that they were partially oxidized due to their high surface energy. Optical absorption, transmission electron microscopy, selective area electron diffraction and XPS of capped nanoparticles (NPs) produced via capping assisted chemical bath deposition using poly(vinyl-pyrrolidone) (PVP) and oleic acid (OA) indicated that narrow size distributed PbS NPs absorbed strongly in the visible region with cubic crystalline phase without any evidence of surface oxidation. Fourier transform infrared spectroscopy of PVP-capped PbS NPs showed strong interaction between PbS NPs and polymer matrix, while for OA-capped PbS NPs, OA was chemically absorbed on the surface of PbS NPs. (c) 2011 Elsevier B.V. All rights reserved.