S. I. Sadovnikov

Synthesis of nanocrystalline silver sulfide

Silver sulfide (Ag2S) powders have been synthesized through chemical precipitation from aqueous solutions of silver nitrate, sodium sulfide, and sodium citrate or Trilon B as a complexing agent and stabilizer. The synthesized Ag2S powders have a monoclinic (sp. gr. P21/c) acanthite (α-Ag2S) structure. The colloidal stock solutions decanted from the synthesized precipitate have been shown to be stable for at least a year. The particle size of the silver sulfide in the colloidal solutions and precipitated powders has been evaluated by dynamic light scattering, X-ray diffraction, and BET measurements. The results demonstrate that, varying the relative reactant concentrations in the starting reaction mixture, one can precipitate Ag2S nanoparticles of tailored average size in the range from ≃ 500 to ≃20–30 nm. The size of Ag2S nanoparticles in the stable colloidal solutions obtained is 15–20 nm.

New Crystalline Phase in Thin Lead Sulfide Films

AbstractThe crystal structure of thin lead sulfide (PbS) films fabricated by hydrochemical deposition is studied by X-ray diffraction analysis. It is established that both the synthesized PbS films and the same films annealed in the temperature interval of 293–423 K have a cubic (space group Fm

Crystal structure of nanostructured PbS films at temperatures of 293-423 K

nbar 3n

One-Pot Synthesis of Lead Sulfide Nanoparticles

m) crystal structure different from the B1-type structure. In this structure, sulfur (S) atoms are located not only in positions 4(b) (octahedral interstices of the face-centered sublattice of lead (Pb) atoms) but also in positions 8(c), i.e., in tetrahedral interstices. The occupations of positions 4(b) and 8(c) by S atoms are ∼0.84 and ∼0.08, respectively. Long-range order in the location of S atoms in positions of each type is absent, but correlations may be present. The new revealed structure of PbS films remains stable under a prolonged annealing in the temperature interval from 293 to 423 K.

Polymorphic transformation in nanocrystalline silver sulfide

Nanocrystalline PbS powders and nanostructured PbS films have been produced by different deposition procedures. According to scanning and transmission electron microscopy results, the average size of PbS particles in the nanopowders is 8 to 20 nm, and the average grain size in the nanofilms is 40 to 80 nm. As shown by electron diffraction, the nanocrystalline PbS powders have the B1 structure (sp. gr.

Stability and recrystallization of PbS nanoparticles

Fmbar 3m