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YPO4:Eu, YVO4:Eu, and YVPO4:Eu based phosphors with various Eu(III) activator contents and phosphate-vanadate ratios were synthesized by the self-propagating high-temperature synthesis method. The samples were characterized by scanning electron microscopy, nitrogen sorption, acid-base indicators and photoluminescence. The particle surface features with a finely dispersed structure comprising all the involved elements. The pore structure and the specific surface areas of the samples were different depending on the compositions of the samples. The most finely dispersed sample was YVO4:Eu samples. The specific surface areas of the YPO4:Eu samples were 10 to 15 times greater than those of vanadate samples. The phosphors samples had a slightly basic (YVO4:Eu, YVPO4:Eu) or slightly acidic (YPO4:Eu) properties of the surface with different contents of Lewis and Brönsted sites. The differences in the compositions and acid-base state resulted in the difference in the intensity and brightness of the photoluminescence (PL) of the samples. The yttrium-phosphate-vanadate phosphors of the mixed YVxP1−xO4-Eu had higher brightness and PL intensity than those samples with similar phosphate as well as vanadate phosphors.

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A technology, that allows production effective x-ray luminescent phosphors Zn3(PO4)2:Mn2+ with nanosized particles from the water solution by sol-gel method, and directional regulated their luminescence color from green to red was developed. X-ray intensity and spectra, phase structure, and surface properties of synthesized samples depending on the synthesis conditions was studied. The conditions of synthesis which allow to obtain the samples according to the demands for the luminophores of medical assignment were determined.

In this Letter, we report the direct streak camera measurements of the duration of a lasing pulse from molecular nitrogen ions under various focusing conditions of 10 mJ, 950 nm femtosecond pump pulse in atmospheric pressure air. The parameters of the active medium are analyzed, and a mechanism for formation of picosecond lasing pulse duration at femtosecond seed pulse duration is proposed.