White‐Light‐Emitting Carbon Dots Prepared by the Electrochemical Exfoliation of Graphite

• Published in: Chemphyschem 2017-02, Vol.18 (3), p.292-298
• Main Authors: Joseph, Julin, Anappara, Aji A.
• Format: Article
• Language: English
• Subjects: Carbon; Diodes; electrochemistry; fluorescence; quantum dots; white-light emission
• ISSN: 1439-4235; 1439-7641
• DOI: 10.1002/cphc.201601020

The single‐step synthesis of white‐light‐emitting carbon dots (CDs) through a green, facile and cheap electrochemical route by using graphite rods as the carbon source is reported. Under UV excitation, the aqueous dispersion of as‐synthesised CDs exhibit broad‐band emission, which covers a significant fraction of the visible spectrum, owing to the heterogeneity in particle size and surface functional groups. The CDs were further explored for their potential as UV‐to‐visible colour convertors under remote‐phosphor technology by capping a λ=365 nm UV light‐emitting diode (LED) chip with CD‐loaded poly(methyl methacrylate) to obtain the following colour parameters: Commission Internationale de l'Eclairage chromaticity coordinates (0.35, 0.37), colour rendering index (88) and correlated colour temperature (4802 K). Rods to dots: The single‐step synthesis of white‐light‐emitting carbon dots (CDs) through a green, facile, and cheap electrochemical route by using graphite rods as the carbon source is reported. Owing to the heterogeneity in particle size and surface functional groups, the CDs can be used as white‐light emitting phosphors coated on a UV light‐emitting diode (see figure).