A study of PbS nanoparticle synthesis via sulfur powder

PbS nanoparticles (NPs) were synthesized by the hot-injection solution-phase method using sulfur powder as precursor. Pb-precursor (446 mg PbO) was dissolved with 1.5 ml oleic acid in 15 ml 1-octadecene (ODE) solvent inside a four-neck flask under N2 atmosphere and nucleated at 120 °C for half an hour. S-precursor (S powder), dissolved in a mixture of 3 ml ODE and 1 ml Oleylamine, was then injected swiftly by a syringe into the flask with well-dissolved Pb-precursor. The growth time varied from 10 minutes to a few hours and growth temperature was maintained at from 90 to 120 °C after injection, which would result in nanoparticles of different sizes from 5 to 10 nm. The synthesized PbS NPs were characterized by TEM, XRD, and UV-Vis-NIR spectrometer. The morphology as well as absorption spectra were found to be highly sensitive to the synthesis conditions. The XRD spectra showed that the structures were less sensitive to synthesis conditions