▎ 摘　　要

NOVELTY - Graphite is dispersed in an organic solution of foaming agent, thermostatically stirred and ultrasonically treated. Obtained mixture is hydrothermally treated at 150-280 degrees C for 330 minutes to 5 hours in oil bath, cooled to room temperature and mixture is added to mixed solution of ethanol and concentrated nitric acid, to obtain suspension. Obtained suspension is hydrothermally treated at 80-160 degrees C for 6-48 hours, cooled, filtered and precipitate is washed and dried. The pH of product is adjusted to 7.5-11 using sodium hydroxide solution, to obtain graphene. USE - Preparation of graphene (claimed). ADVANTAGE - The method efficiently and economically provides graphene with high yield. DETAILED DESCRIPTION - Graphite is dispersed in an organic solution of foaming agent, thermostatically stirred for 30 minutes to 1 hour and ultrasonically treated for 10-30 minutes. The obtained mixture is hydrothermally treated at 150-280 degrees C for 330 minutes to 5 hours in an oil bath, and cooled to room temperature. Then, the mixture is added to mixed solution of ethanol and concentrated nitric acid in volume ratio of 30:1-50:10, to obtain 0.003-0.05 g/mL suspension. The obtained suspension is hydrothermally treated at 80-160 degrees C for 6-48 hours, cooled, filtered and precipitate is washed and dried. The pH of the product is adjusted to 7.5-11 using sodium hydroxide solution at 180-260 degrees C for 30 minutes to 1 hour, to obtain graphene.