Shape-Controlled Preparation of PbS with Various Dendritic Hierarchical Structures with the Assistance of L-Methionine

PbS fishbone-like architectures were synthesized by using a biomolecule (L-methionine)-assisted approach in a mixture solvent made of ethanolamine (EA) and distilled water. Additionally, other PbS homogeneous morphologies (e.g., hexapod-like, coralloid, and dendritic) were obtained through altering the experimental parameters, such as the molar ratio of the reactants and the volume ratio of the mixture solvent. It is noteworthy that our experiments were envionmentally friendly, because no disgusting scent (H.)S) appeared in our experiments, which could be hardly avoided in other previous reports. The as-prepared PbS products were examined by using XRD, FESEM, TEM, HRTEM, SAED, and PL. Furthermore, a possible growth mechanism (an initial nucleating stage and a subsequent growth stage) was proposed to explain the formation of dendritic architectures on the basis of TEM observations, XRD, and FTIR analyses. Up to now, this is the first case of the direct growth of novel PbS with various hierarchical nanostructures with L-methionine's assistance. The synthesized PbS fishbone-like structure was found to indicate strong photoluminescence in the blue-light range.