METHOD OF PRODUCING HIGHLY CONCENTRATED ORGANOSOL OF SILVER NANOPARTICLES Russian patent published in 2024 - IPC B22F1/545 B22F1/107 B22F9/24 B01J13/00 B82Y40/00 B01D11/02 C01G5/00 

FIELD: various technological processes.

SUBSTANCE: invention can be used in production of optical devices, chemical and biological sensors, catalysts, antibacterial materials, inks for 2D- and 3D-printing, electroconductive and heat-conducting materials, plasma and liquid crystal displays, solar cells. Method of producing highly concentrated organosol of silver nanoparticles involves reduction of an aqueous solution of silver nitrate. Concentration of silver nitrate in the initial solution is 0.6 M. Reducing agent used is a mixture of solutions of iron (II) sulphate and trisodium citrate. Sodium citrate and silver nitrate solutions are alternately added to the FeSO₄ solution until a molar ratio of 1:1:(1.5÷3.2) is achieved. Obtained precipitate is separated by centrifugation and washed with a solution of trisodium citrate, again centrifuged, the operation is repeated 3-4 times. Coagulate of nanoparticles is peptized in distilled water with formation of hydrosols of silver nanoparticles. Extraction of silver metal nanoparticles is carried out from aqueous solutions into the phase of o-xylene or butyl acetate in the presence of ethyl alcohol and cetyltrimethylammonium bromide or cetyltrimethylammonium nitrate. Obtained silver organosol is separated by decantation and concentrated by distillation of the solvent to a metal concentration of up to 1,800 g/l.

EFFECT: invention simplifies synthesis of silver nanoparticles of spherical morphology with low polydispersity and increases efficiency thereof.

1 cl, 9 dwg, 3 ex