METHOD FOR PRODUCTION OF NANO-DIMENSIONAL HIGH-LUMINESCENT APATITE WITH EUROPIUM (EU) IMPURITY Russian patent published in 2017 - IPC C09K11/71 C09K11/78 C09K11/81 B82B3/00 B82Y40/00 

FIELD: chemistry.

SUBSTANCE: first, aqueous solutions containing Ca2⁺ and Eu³⁺ cations are mixed while controlling their concentration and ratio in the solution. Nitrates of these elements are taken as Ca2⁺ and Eu³⁺ sources. Calcium nitrate is taken at a concentration of 1 mol/l and in an amount of 20 ml, and europium nitrate is taken at a concentration of 0.02 mol/l and in an amount of 5-50 ml, which corresponds to the Eu/Ca molar ratio of 0.5-5%. The solution volume is adjusted to 100 ml with distilled water. Simultaneously, an aqueous solution containing phosphate anions is prepared with control of their concentration, using a mixture of 12 ml of potassium dihydrogen phosphate at a concentration of 1 mol/l and 10 ml of a KOH solution with a concentration of 1.4 mol/l. The second solution is adjusted to 100 ml and pH of 11-12 with distilled water. Each of the prepared solutions is heated to 90°C, taken in the volume of 100 ml and mixed with vigorous stirring. The mixed solution is then kept at 90°C for 2-3 hours, cooled and precipitate is separated from the solution, which is washed at least 6 times with distilled water in a volume of at least 400 ml. The washed precipitate is dried at a temperature of 110°C for 6-7 hours. The resulting nanoscale high-luminescent apatite with an europium (Eu) admixture has a luminescence intensity of up to 3500000 rel. units, which is the maximum possible value for luminescent apatites containing europium.

EFFECT: increased intensity of luminescence.

4 dwg, 3 tbl, 3 ex