Scalable synthesis of highly photoluminescence carbon quantum dots

[Display omitted] •A rapid, scalable synthesis of carbon quantum dots is demonstrated.•Carbon quantum dots are formed in glycerol by simply heating.•The absorption and emission properties are dominated by surface fluorophores.•Ten-gram scale is possible per bath synthesis. Scaling up the synthesis carbon quantum dots (CQDs) is highly demanded for the deployment of CQDs in diverse applications. Herein, we used glycerol (Gly) as high boiling point solvent that enables scalable synthesis of CQDs from mixtures of citric acid (CA) and ethylenediamine (EDA) within few minutes by either thermal heating or microwave. Purified CQDs were spherical with a diameter varying from 2 to 8 nm. The CQDs exhibited a resolved UV absorption band at about 346 nm and a broad photoluminescence (PL) spectrum with a PL quantum yield of 49.9%.