METHOD FOR SYNTHESIS OF NaYF:Er,Yb UPCONVERSION PARTICLES Russian patent published in 2020 - IPC C09K11/55 C09K11/61 C09K11/77 

FIELD: physics; medicine.

SUBSTANCE: invention can be used in biophysics, medical diagnostics and therapy for converting infrared radiation into visible radiation. Water solutions of hexahydrates of yttrium chloride, ytterbium chloride, erbium chloride, as well as sodium citrate and sodium fluoride are prepared. Obtained solutions of hexahydrates of yttrium chloride, ytterbium chloride and erbium chloride are mixed. Obtained mixture is added with an aqueous solution of sodium citrate with molar content of not less than 2.98 M in an amount of not less than 29.0 moles per 1 mole of the total amount of said hexahydrates, followed by stirring for 30–60 minutes. Then, aqueous solution of sodium fluoride is added to the mixture in an amount of not less than 4 moles per 1 mole of total amount of said hexahydrates and mixed again for 30–60 minutes. Obtained reaction mixture is held at a temperature of not less than 160 °C and not more than 200 °C for 2–12 h in sealed conditions to form particles of a given size, which are then separated, washed and dried. Upconversion luminophor has the chemical formula NaYF₄:Er,Yb, particle size of not more than 500 nm while maintaining low defectiveness of their surface.

EFFECT: disclosed method enables to reduce time and temperature of synthesis of said luminophor.

1 cl, 4 dwg, 1 tbl