Abstract
Figure Persented: Glucose-derived water-soluble crystalline graphene quantum dots (GQDs) with an average diameter as small as 1.65 nm (∼5 layers) were prepared by a facile microwave-assisted hydrothermal method. The GQDs exhibits deep ultraviolet (DUV) emission of 4.1 eV, which is the shortest emission wavelength among all the solution-based QDs. The GQDs exhibit typical excitation wavelength-dependent properties as expected in carbon-based quantum dots. However, the emission wavelength is independent of the size of the GQDs. The unique optical properties of the GQDs are attributed to the self-passivated layer on the surface of the GQDs as revealed by electron energy loss spectroscopy. The photoluminescence quantum yields of the GQDs were determined to be 7-11%. The GQDs are capable of converting blue light into white light when the GQDs are coated onto a blue light emitting diode.
Original language | English |
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Pages (from-to) | 5102-5110 |
Number of pages | 9 |
Journal | ACS Nano |
Volume | 6 |
Issue number | 6 |
DOIs | |
Publication status | Published - 26 Jun 2012 |
Keywords
- deep ultraviolet
- fluorescence
- grapheme
- graphene quantum dots
- quantum dots
- self-passivated
ASJC Scopus subject areas
- General Materials Science
- General Engineering
- General Physics and Astronomy