▎ 摘　　要

NOVELTY - Synthesis of monodispersed graphene quantum dots, comprises (a) heating the starting material at 190-210 degrees C followed by sonication in de-ionized water for 30 minutes to obtain a light brownish to dark brownish color solution, and (b) filtering solution of step (a) through porous membrane, washing and dialyzing the filtrate for 2-3 days in acidic medium to obtain purified graphene quantum dots. The starting material is rice powder obtained after grinding rice grains pre-cleaned with de-ionized water. USE - The method is useful for synthesis of monodispersed graphene quantum dots. ADVANTAGE - The method: excludes addition of any surfactant, additive or chemicals resulting in pristine graphene quantum dots; provides graphene quantum dots which are in quantum confinement range, exhibiting strong fluorescence at 360 nm by exhibiting a red shift (from blue to cyan) with increase in size of 1-6.5 nm; provides quantum yield of is 16-24% with increase in quantum yield with increase in size of graphene quantum dots resulting from decrease in defect related emissive sites (claimed); is cheaper, efficient, does not involve any complex steps and is environmentally benign method which synthesizes size controlled graphene quantum dots using natural resources while ensuring that at the same time the properties of the graphene quantum dots are not comprised.