Water-soluble, biocompatible, and highly luminescence carbon quantum dots (CQDs) have synthesized successfully from a citric acid (CA) and ethylenediamine (EDA) by using different approaches. Although the emission quantum yield of CQDs could be as high as 80% their emission spectrum is usually dominated by surface fluorophore groups and maximized at about 450 nm. Herein, we examined the effects of acid and amine precursors on the photoluminescence (PL) of resulting CQDs by systematic comparison the optical properties of CQDs obtained from CA, PA (phthalic acid) and EDA, ANL (aniline). UV-vis and PL spectroscopic studies revealed that the absorption onset varied from 325 nm to 400 nm while PL maximum changed from 390 nm to 450 nm by engineering acid and amine precursors. The emission quantum yield was also changed from 9 to 70%, depending on the used acid-amine precursors.
Keywords
Carbon quantum dots, hydrothermal synthesis, color tuning, photoluminescence, acid, amine
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Tuning the Emission Color of Hydrothermally Synthesized Carbon Quantum Dots by Precursor Engineering