Deep ultraviolet to near-infrared emission and photoresponse in layered n-doped graphene quantum dots

Libin Tang, Rongbin Ji, Xueming Li, Gongxun Bai, Chao Ping Liu, Jianhua Hao, Jingyu Lin, Hongxing Jiang, Kar Seng Teng, Zhibin Yang, Shu Ping Lau

Research output: Journal article publicationJournal articleAcademic researchpeer-review

349 Citations (Scopus)


Material that can emit broad spectral wavelengths covering deep ultraviolet, visible, and near-infrared is highly desirable. It can lead to important applications such as broadband modulators, photodetectors, solar cells, bioimaging, and fiber communications. However, there is currently no material that meets such desirable requirement. Here, we report the layered structure of nitrogen-doped graphene quantum dots (N-GQDs) which possess broadband emission ranging from 300 to >1000 nm. The broadband emission is attributed to the layered structure of the N-GQDs that contains a large conjugated system and provides extensive delocalized π electrons. In addition, a broadband photodetector with responsivity as high as 325 V/W is demonstrated by coating N-GQDs onto interdigital gold electrodes. The unusual negative photocurrent is observed which is attributed to the trapping sites induced by the self-passivated surface states in the N-GQDs.
Original languageEnglish
Pages (from-to)6312-6320
Number of pages9
JournalACS Nano
Issue number6
Publication statusPublished - 24 Jun 2014


  • broadband emission
  • graphene quantum dot
  • nitrogen doping
  • photoluminescence
  • photoresponse

ASJC Scopus subject areas

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

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