Carbon quantum dots: Synthesis and correlation of luminescence behavior with microstructure

doi:10.1016/S1872-5805(21)60031-8

New Carbon Materials

Volume 36, Issue 3, June 2021, Pages 625-631

https://doi.org/10.1016/S1872-5805(21)60031-8 Get rights and content

Abstract

Two kinds of carbon quantum dots, C-dots-160 and C-dots-200 with different fluorescence luminescence behaviors were synthesized by a one-step hydrothermal method at 160 and 200 °C, respectively, using ammonium citrate as the raw material. The relationship between the microstructure of the C-dots and the fluorescence emission behavior was investigated. Results indicate that an increase of synthesis temperature introduces more oxygen and nitrogen atoms into the C-dots, increasing the total number of structural defects and altering their concentration ratio. It is this ratio difference in the two C-dots that causes their different luminescence behaviors. The proportion of several types of defects in the C-dots-200 are relatively balanced, leading to excitation wavelength-dependent fluorescence while the most abundant defects in C-dots-160 are in the form of C=O, which is the main reason for its excitation independent luminescence behavior. The number of structural defects in C-dots-160 is less than in C-dots-200 and the latter has the stronger fluorescence emission.

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Citation Excerpt :
Next, the supernatant was dialyzed with 1000 Da dialysis bag for 36 h. The purified dialysis clear liquid was freeze-dried to acquire a cream solid powder and stored in refrigerator (4 °C) for further use [49]. The recognition of Cu2+ and Cys were investigated in aqueous N-CQDs solution at pH = 7.4 at ambient temperature, using PBS.
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RESEARCH PAPERCarbon quantum dots: Synthesis and correlation of luminescence behavior with microstructure

Abstract

Materials Letters

Materials Letters

Scientific Reports

Quantum-sized carbon dots for bright and colorful photoluminescence [J]

Journal of the American Chemical Society

Carbon quantum dots and their biomedical and therapeutic applications: a review [J]

RSC Advances

Water-soluble fluorescent carbon quantum dots and photocatalyst design [J]

Angewandte Chemie International Edition

Nitrogen-doped carbon dots for “green” quantum dot solar cells [J]

Nanoscale Research Letters

RESEARCH PAPER
Carbon quantum dots: Synthesis and correlation of luminescence behavior with microstructure