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Lead sulfide (PbS) quantum dots (QDs) capped with oleic acid and oleic amine were synthesized by using safe and innocuous sulfur powder as S source instead of the bis (trimethylsilyl) sulfide ((TMS)₂S). QDs with size distribution from 20 nm to 3 nm were gained by controlling the experiment parameters such as heating temperature, capping agents and the growth time. The morphology and crystal structure of the as-prepared PbS QDs were characterized by (high-resolution) transmission electron microscopy (HR-TEM) images and powder X-ray diffraction (XRD). This method may offer a new route to synthesize PbS QDs for photovoltaic devices.

Nanoparticle Lead sulfide was synthesized via simple chemical method and deposited on glass substrates at different substrate temperatures by thermal evaporation technique. The synthesized nanoparticle PbS was analyzed and confirmed by X-ray diffraction (XRD), Scanning electron microscopy SEM with EDX and thermogravimetry. The structural, optical, morphological and electrical properties of the deposited films were studied using XRD, UV-Vis, Raman, SEM with EDX, atomicforce microscopy AFM and Hall Effect measurements. The thickness of the deposited samples was measured using thickness profilometer. The Raman shift in the peak occurs toward lower energy with increasing substrate temperature deposited lead sulfide. The Z-scan study with open aperture was carried out at 532 nm using 5 ns laser pulse on the deposited films which shows that nonlinear absorption arises from saturable absorption process. The deposited PbS film exhibits p-type conductivity in Hall measurement.

Iron-doped lead sulfide thin films were deposited on glass substrates using successive ionic layer adsorption and reaction method (SILAR) at room temperature. The X-ray diffraction pattern of the film shows a well formed crystalline thin film with face-centered cubic structure along the preferential orientation (1 1 1). The lattice constant is determined using Nelson Riley plots. Using X-ray broadening, the crystallite size is determined by Scherrer formula. Morphology of the thin film was studied using a scanning electron microscope. The optical properties of the film were investigated using a UV–vis spectrophotometer. We observed an increase in the optical band gap from 2.45 to 3.03eV after doping iron in the lead sulfide thin film. The cutoff wavelength lies in the visible region, and hence the grown thin films can be used for optoelectronic and sensor applications. The results from the photoluminescence study show the emission at 500–720nm. The vibrating sample magnetometer measurements confirmed that the lead sulfide thin film becomes weakly ferromagnetic material after doping with iron.

Lead sulfide quantum dots (QDs) were prepared by liquid phase method. The particle size can be controlled by changing the concentration of reactants and surfactant and the size of the QDs varies from 7nm to 20nm, which results in the change of the optical properties and the band gap of the particles. The optical band gap of lead sulfide QDs increased drastically with the decrease of the diameter of the sample QDs.