METHOD FOR OBTAINING OXIDE AP-CONVERSION LUMINOPHERS Russian patent published in 2021 - IPC C09K11/78 C09K11/66 C09K11/68 

FIELD: inorganic chemistry.

SUBSTANCE: invention relates to the field of inorganic chemistry, namely to a method for producing oxide up-conversion luminophores with luminescence in the visible region of the spectrum. The method consists in preparing an aqueous solution containing nitrates of rare earth elements, ammonium molybdate (NH₄)₆Mo₇O₂₄, a germanium precursor and citric acid so that metal cations are in stoichiometric amounts, and citric acid is in excess, the resulting solution is evaporated at 80°C until the formation of a gel and dried, then annealed at high temperatures with grinding the product between annealing. Salts of gadolinium, ytterbium and erbium are used as nitrates of rare-earth elements, with the molar ratio of Yb³⁺:Er³⁺ being from 7:4 to 9:4. An aqueous solution of GeO₂ in (СН₃)₄NOH is used as a solution of the germanium precursor. The molar ratio of the total amount of metals to citric acid is 1:1.5-1:2. Before evaporation, mannitol is added to the resulting solution so that the molar ratio of citric acid : mannitol = 3:2, the gel is dried at 200°C, annealing is carried out with gradual heating from room temperature, the annealing temperatures are 700°C, 1000°C and 1200°C with exposure at each stage for 4-5 hours.

EFFECT: invention provides possibility to obtain oxide up-conversion luminophores based on the Gd₂GeMoO₈ matrix, which upon IR excitation luminesce in the visible region of the spectrum and which can be used in various fields where IR excitation is required, including for the creation of alternative light sources, thermal sensors and luminescent biomarkers.

1 cl, 3 dwg, 4 ex