Some features of luminescent properties of PbS suspensions, stabilized by high‐molecular polyvinylpyrrolidone

Abstract

The results of the investigations of optical and luminescent properties of PbS suspensions stabilized by highmolecular polyvinylpyrrolidone are described. Suspensions prepared by liquid colloidal method from sodium sulfide and lead nitrate demonstrate strong luminescence in near infrared spectral range at the excitation by visual light with different wavelengths. It was proposed that Förster resonant energy transfer plays the important role in luminescence properties of closed packed PbS particles. The model, which describes the observed luminescent properties of the suspensions PbS-stabilized high-molecular polymer, is proposed. The combination of very wide spectral range of excitation of the luminescence with rather narrow range of light radiation in near infrared spectral range determine wide perspectives of the materials in solar luminescent concentrators and photodetectors.

Stabilization of PbS quantum dots by high molecular polyvinylpyrrolidone

“…It can be seen that there are no absorption bands in visible range. The observed shape of the spectra can be explained by the wide distribution of QD sizes [2,14] that can be attributed to the specificity of QD prepared by the wet colloidal synthesis. [23] The intensive absorption band of liquid phase is observed near 1170 nm.…”

“…The details of the synthesis of PbS QD suspensions were described in Bagrov et al [14] The content of PbS in all prepared suspensions was 1,6 · 10 -4 mol/l. The molar ratios between PbS and PVP ([PbS]/ [PVP]) in our suspensions were 210 (suspension 1); 1100 (suspension 2); 2100 (suspension 3); and 1000 (suspension 4).…”

“…[10,11,[13][14][15][16][17][18][19][20][21] In addition, PVP molecules are able to participate in energy-transfer processes, expending luminescence excitation spectra in ultraviolet spectral range and considerably increasing luminescent intensity of ZnS nanocrystals doped by Mn 2+ or Cu + /Al 3+ .…”

“…The PbS QD is often prepared by wet chemical synthesis in the presence of organic‐stabilizing component . The chemical nature of stabilizing agent strongly affects the properties of QD suspensions prepared …”

Immersion film-forming compositions based on high-molecular polyvinylpyrrolidone

“…The presence of PbS or ZnS nanocrystals increases the refractive index of immersion compositions. The methods of the preparation and stabilization of these nanocrystals were described in detail . At first stage of the synthesis aqueous solution of lead (or zinc), nitrate was mixed with the solution of PVP in propanol‐2 at room temperature.…”