METHOD OF PRODUCING NANOSIZED DIAMONDS Russian patent published in 2019 - IPC C01B32/26 B82B3/00 B01J3/06 B82Y40/00 

FIELD: physics; medicine.

SUBSTANCE: invention can be used in quantum physics, biology and medicine. Mixture of powders of hydrocarbons and alloying additives is prepared, in which the powder of ultrafine diamond with a particle size of 3–4 nm is additionally injected. Naphthalene or adamantane is taken as hydrocarbon powders, and tetrakis (trimethylsilyl) silane and tetraphenylgermanium are used as dopants. Components of the mixture of hydrocarbon - ultrafine diamond - alloying additive is taken in a weight ratio of 1:(2–2.5):(0.16–1.7). Resulting mixture is ground to a uniform state and a sample is prepared from it by pressing under pressure from 2.0 to 3.0 t/cm². Prepared sample is subjected to a pressure of 8–9 GPa and a temperature of 1200–1500 °C with an exposure at the specified parameters for 3–20 seconds. Then the temperature is reduced to room temperature, after which the pressure is reduced to atmospheric. Resulting sample is treated by boiling in a mixture of sulfuric, nitric and perchloric acids, taken in a 1:1:1 ratio for 5–10 hours, and washed with distilled water. Synthesized nano-sized diamonds are divided into an ultrananosized fraction of less than 10 nm and a nano-size fraction of 10–100 nm by ultrasonic dispersion in liquid media and subsequent multi-stage centrifugation of the resulting dispersions.

EFFECT: yield of both nanoscale and ultrananosized fractions with a given content of optically active vacancy-containing centers such as SiV and GeV increases.

1 cl, 10 dwg, 5 ex