DOUBLE SODIUM-BISMUTH MOLYBDATE, AND ITS PRODUCTION METHOD Russian patent published in 2022 - IPC C01G39/00 C01G29/00 C01D13/00 H01S3/16 C09K11/55 C09K11/68 C09K11/74 B82Y30/00 B82Y40/00 

FIELD: chemistry.

SUBSTANCE: invention relates to a chemical technology for the production of an inorganic compound – sodium-bismuth molybdate with a scheelite structure, which is perspective material as a matrix for luminescent devices, such as white glow LEDs, gas-discharge membranes, separators, sensors, and fuel cells. Double sodium-bismuth molybdate of a composition Na₅Bi(MoO₄)₄ is proposed as a matrix for laser material. A method for the production of Na₅Bi(MoO₄)₄ includes the dissolution in distilled water of crystal powder of sodium molybdate Na₂MoO₄ and crystal powder of ammonium hexamolybdate (NH₄)₆Mo₇O₂₄⋅4H₂O, at a ratio (mol): Na₂MoO₄:(NH₄)₆Mo₇O₂₄⋅4H₂O equal to 1.25:0.107, at a temperature of 50-60°C, and mixing with subsequent evaporation to a dry residue, dissolution of bismuth oxide Bi₂O₃ in nitric acid HNO₃ with a concentration of 40.34%, at a ratio (mol): Bi₂O₃:HNO₃ equal to 0.25:(7.7÷8.0), at a temperature of 35-40°C, and mixing with subsequent evaporation to a dry residue, combination of residues, and addition of formic acid HCOOH with a concentration of 99.7%, at a ratio (mol): sodium molybdate:ammonium hexamolybdate:bismuth oxide:formic acid equal to 1,25:0,107:0,25:(26÷29), at a temperature of 30-35°C, with subsequent exposure to a temperature of 80-100°C to complete evaporation, then, the resulting dry residue is subjected to annealing in three stages: I stage – at a temperature of 350-360°C for 7-8 h; II stage – at a temperature of 430-440°C for 5-6 h; III stage – at a temperature of 455-460°C for 3-4 h, with reshaping and pressing into tablets under pressure of 50 bar after the second stage.

EFFECT: method differs in universality, reproducibility, and allows for the production of single-phase compositions of bismuth-sodium molybdates in a high-dispersed state without participation of toxic organic compounds, while providing the expansion of the range of materials used as a laser matrix.

2 cl, 2 dwg, 2 ex