Fluorophosphate Glasses Containing PbSe Quantum Dots

The specific features in the formation of IV–VI (PbSe) quantum dots in a vitreous fluorophosphate matrix are investigated by X-ray microanalysis, high-resolution scanning transmission electron microscopy (STEM), high-resolution X-ray diffraction, and optical absorption spectroscopy. A complete characterization of the quantum dots grown (their sizes, morphology, and distributions over the matrix bulk and sizes) in the glass is performed on the basis of the results obtained. The inference is made that spherical PbSe nanocrystals with a cubic lattice of the NaCl type are formed in fluorophosphate glasses. The nanocrystals are uniformly distributed over the matrix bulk and are characterized by a narrow size distribution (ΔR/R ≈ 7%) in the studied size range R ≈ 1.8–10 nm, which corresponds to strong quantum confinement. It is noted that the mechanism of the quantum-dot growth in the glasses under consideration differs from the mechanisms studied earlier in glasses of silicate systems.