PbS nanostructures: thermal decomposition synthesis of [bis(thiosemicarbazide)lead(II)] precursor

[Pb(TSC)2]Cl2 (TSC = thiosemicarbazide) was used as a single source precursor for the synthesis of PbS nanoparticles. The nanoparticles were synthesized in the presence of oleylamine and triphenylphosphine, as surfactant, at 210 ˚C. During thermal decomposition reaction, nucleation rate for the nanocrystals can reach a high value in a short time and the nuclei are wrapped by surfactant [1]. Consequently, the formed nanocrystals grow to a certain value and saturation. The effect of the surfactant is to control the size of the particles and prevent the aggregation of them. The products were characterized by using XRD. All of the XRD peaks can be indexed to the cubic PbS without obvious characteristic reflection peaks from other impurities, PbS = JCPDS No. 78-1898, with the lattice parameter a = 5.918A˚. The broadening peaks caused by the small size of PbS nanocrystals. The size of PbS nanocrystals calculated from the Scherrer formula is 35 nm. The morphology and structure of the as-prepared PbS nanparticles were investigated by SEM and TEM. Results show formation of the uniform PbS spherical nanoparticles. TEM was in good agreement with the calculated particle size from SEM, 50 nm. Also FT-IR and PL spectra of the products were investigated [2].