Hydrothermal Synthesis of Photoluminescent Nanocarbon from Hydroxylic Acids and Amines

Abstract: Carbon dots (CDs) were synthesized from various pairs of hydroxylic acids and amines under hydrothermal conditions. Citric acid (CA) was paired with ethylenediamine (EDA) and the methylated analogues, and malic acid (MA), tartaric acid (TA) and mucic acid (MuA) were coupled with EDA. While the CDs from CA with EDA show strong photoluminescence, CA paired with the methyl-capped EDA derivatives gives less photoluminescent nanocarbons with a similar size of ~2 nm. The CDs from MA and TA with EDA show emission at shorter wavelengths than those from CA and MuA. The quantum yields of the CDs from CA and MA with EDA increase with the reaction time, which may be explained by modifications of the chemical structures of the CDs. Graphical Abstract: [Figure not available: see fulltext.] © 2016, Springer Science+Business Media New York