Deep ultraviolet photoluminescence of water-soluble self-passivated graphene quantum dots

Libin Tang, Rongbin Ji, Xiangke Cao, Jingyu Lin, Hongxing Jiang, Xueming Li, Kar Seng Teng, Chi Man Luk, Songjun Zeng, Jianhua Hao, Shu Ping Lau

Research output: Journal article publicationJournal articleAcademic researchpeer-review

1192 Citations (Scopus)

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 languageEnglish
Pages (from-to)5102-5110
Number of pages9
JournalACS Nano
Volume6
Issue number6
DOIs
Publication statusPublished - 26 Jun 2012

Keywords

  • deep ultraviolet
  • fluorescence
  • grapheme
  • graphene quantum dots
  • quantum dots
  • self-passivated

ASJC Scopus subject areas

  • Materials Science(all)
  • Engineering(all)
  • Physics and Astronomy(all)

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