Facile synthesis of PbS, Bi2S3 and Bi-doped PbS nanoparticles from metal piperidine dithiocarbamates complexes

Abstract

Single source precursors are advantageous starting materials to the syntheses of nanomaterials. In this study, lead and bismuth piperidine dithiocarbamate complexes have been synthesized and used as efficient precursors for synthesizing PbS and Bi2S3 nanoparticles using hot injection techniques. The bismuth piperidine dithiocarbamate complex was then used as a dopant to form Bi-doped PbS nanoparticles. Alloys are functional materials for present day applications. In the energy sector, they allow for band gap engineering and size dependent quantum confinement effects. The p-XRD pattern of the PbS was indexed to a cubic rocksalt structure, whereas the Bi2S3 was indexed to an orthorhombic structure. The morphological studies using the TEM revealed the formation of cubes and rods for the PbS and Bi2S3, respectively. An interplay of these structures was observed for the alloy depending on the mole fraction of Bi doping in the injected precursor solution. The optical band gaps were blue-shifted to 0.72 and 1.94 eV for PbS and Bi2S3, respectively. The Bi-doped PbS nanoparticles displayed optical band gaps in between the binary materials.