METHOD FOR SCALING SYNTHESIS OF GRAPHENE OXIDE Russian patent published in 2022 - IPC C01B32/198 B82B3/00 B82Y40/00 

FIELD: chemistry.

SUBSTANCE: invention relates to a method for scaling the synthesis of graphene oxide, including the dispersion of graphite powder in concentrated sulfuric acid. Next, potassium permanganate is added to the resulting mixture, it is diluted with distilled water, a precipitate is filtered and washed to a neutral pH value, followed by drying. The method is characterized by that, additionally, when dispersing graphite powder in concentrated sulfuric acid, phosphorus oxide (V) is added, then, the resulting mixture is treated with ultrasound for 10 min, and, after addition of potassium permanganate, sodium nitrate is added to the mixture. After dilution of the mixture with distilled water, a temperature of the mixture is increased to 95°C for 1.5 h, followed by the addition of additional amount of distilled water and 30% of H₂O₂, filtration of the precipitate is carried out on a Schott filter. Then, the resulting precipitate is washed with distilled water, followed by drying at a temperature of 65°C for 5 h, and dispersed in distilled water in an ultrasound bath for 1 h. At the same time, a number of reagents is calculated in such a way that the amount of sulfuric acid is 5 times higher than the initial amount of graphite powder, while its initial amount is 10 times higher than the amount of phosphorus oxide (V), sodium nitrate, and hydrogen peroxide, dilution of the mixture, before raising its temperature to 95°C, with distilled water is performed in amount 2.5 times higher than the initial amount of graphite powder. After this, the mixture is dispersed in distilled water in amount exceeding the initial amount of graphite powder by 5 times.

EFFECT: development of a scalable method for the synthesis of graphene oxide with an increased content of oxygen-containing functional groups (up to 85%) by use of additional oxidants and selection of technological modes, which allow further modification of the graphene oxide surface and obtaining stable aqueous dispersions.

1 cl, 11 dwg, 1 tbl, 1 ex