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Tuning the Photoluminescence of Graphene Quantum Dots by Photochemical Doping with Nitrogen.

ABSTRACT: Nitrogen-doped graphene quantum dots (NGQDs) were synthesized by irradiating graphene quantum dots (GQDs) in an NH₃ atmosphere. The photoluminescence (PL) properties of the GQDs and the NGQDs samples were investigated. Compared with GQDs, a clear PL blue-shift of NGQDs could be achieved by regulating the irradiating time. The NGQDs obtained by irradiation of GQDs for 70 min had a high N content of 15.34 at % and a PL blue-shift of about 47 nm. This may be due to the fact that photochemical doping of GQDs with nitrogen can significantly enhance the contents of pyridine-like nitrogen, and also effectively decrease the contents of oxygen functional groups of NGQDs, thus leading to the observed obvious PL blue-shift.

SUBMITTER: Xu X

PROVIDER: S-EPMC5706275 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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Tuning the Photoluminescence of Graphene Quantum Dots by Photochemical Doping with Nitrogen.

Xu Xiaofen X Gao Fuhua F Bai Xiaohua X Liu Fuchi F Kong Wenjie W Li Ming M

Materials (Basel, Switzerland) 20171120 11

Nitrogen-doped graphene quantum dots (NGQDs) were synthesized by irradiating graphene quantum dots (GQDs) in an NH₃ atmosphere. The photoluminescence (PL) properties of the GQDs and the NGQDs samples were investigated. Compared with GQDs, a clear PL blue-shift of NGQDs could be achieved by regulating the irradiating time. The NGQDs obtained by irradiation of GQDs for 70 min had a high N content of 15.34 at % and a PL blue-shift of about 47 nm. This may be due to the fact that photochemical dopin ...[more]

PMID: 29156648

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