Journal
CARBON
Volume 193, Issue -, Pages 205-215Publisher
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.carbon.2022.03.019
Keywords
Sorted graphene quantum dot; Excitation-wavelength-independent; photoluminescence; Near-infrared-II excitation; Two-photon ultraviolet-near-infrared; bioimaging; Two-photon photodynamic inactivation
Funding
- AN Nan Hospital, China Medical University, Taiwan [ANHRF110-33]
- State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, Guangxi Normal University, China [CMEMR2021-B11]
- Ministry of Science and Technology, Taiwan [MOST 110-2221-E-006-013-MY3, MOST 109-2636-E-006-018]
- Academia Sinica Healthy Longevity Grand Challenge Competition, Taiwan [AS-HLGC-110-07]
- Allergy Immunology and Microbiome Center, China Medical University Children's Hospital/China Medical University Hospital, China Medical University, Taiwan [1JA8]
- E-Da Hospital, Taiwan
Ask authors/readers for more resources
By chemically modifying graphene quantum dot materials through nitrogen doping and amino-group functionalization, this study improved electron donation efficiency, enhancing absorption, luminescence, radiative efficiency, and other properties.
Nitrogen doping and amino-group functionalization through chemical modification can engender enhance electron donation. Using a homemade femtosecond titanium:sapphire laser optical system operated at a low energy and short photoexcitation time [power: 200.0 nJ pixel-1; scanning frequency: 150 scans (~0.80-1.33 s); excitation wavelength: 870, 910, or 970 nm], this study conducted these processes on the large is-conjugated system of graphene quantum dot (GQD)-based materials functioning as electron donors; this improved the efficiency of charge transfer to the prepared amino-NGQDs, resulting in enhanced two-photon absorption, excitation-wavelength-independent photoluminescence (EWI-PL), radiative efficiency, excitation absolute cross section, and excitation from the near-infrared (NIR)-I to the NIR-II region. The lifetime decreased and quantum yield (QY) increased. The sorted amino-N-GQDs exhibited two-photon EWI-PL emissions between the ultraviolet and NIR-I regions, leading to the generation of reactive oxygen species (ROS), which functioned as two-photon photosensitizers for photodynamic therapy (PDT). Increasing the mean lateral size of the particles increased the N-functionality-dependent photochemical and electrochemical activities, which improved the PL QY and thus enhanced the efficiency of two-photon PDT. Additionally, a polystyrene sulfonate (PSS) coating was applied (forming sorted amino-N-GQD-PSS); the sulfur atoms introduced by the PSS induced the radiative recombination of localized electron-hole pairs and then improved the sorted amino-N-GQD surfaces by strengthening the quantum confinement of their emissive energy. Thus, compared with the sorted amino-N-GQDs that were not coated, the PSS-coated materials had superior two-photon properties. No ROS were detected. Accordingly, these materials are suitable for use as two photon contrast probes for analyte tracking and localization.(C) 2022 Elsevier Ltd. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available