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Size Effect of Graphene Quantum Dots on Photoluminescence.

ABSTRACT: High-photoluminescence (PL) graphene quantum dots (GQDs) were synthesized by a simple one-pot hydrothermal process, then separated by dialysis bags of different molecular weights. Four separated GQDs of varying sizes were obtained and displayed different PL intensities. With the decreasing size of separated GQDs, the intensity of the emission peak becomes much stronger. Finally, the GQDs of the smallest size revealed the most energetic PL intensity in four separated GQDs. The PL energy of all the separated GQDs shifted slightly, supported by density functional theory calculations.

SUBMITTER: Liu Z

PROVIDER: S-EPMC8271461 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

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Size Effect of Graphene Quantum Dots on Photoluminescence.

Liu Ziyi Z Li Fei F Luo Yi Y Li Ming M Hu Guanghui G Pu Xianjuan X Tang Tao T Wen Jianfeng J Li Xinyu X Li Weitao W

Molecules (Basel, Switzerland) 20210626 13

High-photoluminescence (PL) graphene quantum dots (GQDs) were synthesized by a simple one-pot hydrothermal process, then separated by dialysis bags of different molecular weights. Four separated GQDs of varying sizes were obtained and displayed different PL intensities. With the decreasing size of separated GQDs, the intensity of the emission peak becomes much stronger. Finally, the GQDs of the smallest size revealed the most energetic PL intensity in four separated GQDs. The PL energy of all th ...[more]

PMID: 34206960

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