Engineering Ultrastable Intrinsic Radicals: Graphene Quantum Dots With NIR‐II Emission for Dynamic Deep‐Tissue Bioimaging
- 1State Key Laboratory of Digital Medical Engineering Key Laboratory of Biomedical Engineering of Hainan Province School of Biomedical Engineering Hainan University Sanya China
- 2Joint Key Laboratory of the Ministry of Education Institute of Applied Physics and Materials Engineering University of Macau Taipa Macau SAR China
- 3Interdisciplinary Institute of Medical Engineering Fuzhou University Fuzhou China
Abstract
Stable radicals in carbon‐based materials have witnessed great consideration in the field of photonic and quantum information technologies, yet their development has been hindered by inherent instability arising from high reactivity. Here, we demonstrate the stabilization of intrinsic radicals within graphene quantum dots (GQDs) synthesized via two‐dimensional polymerization of perylene derivatives. Numerous radicals are stably localized at periodically arranged lattice defects in bilayer graphene‐like plates, where the induced structural distortions and intralayer oscillations minimize interlayer interactions, thus enabling exceptional radical stability across a broad temperature range (100–500 K). This configuration generates an intrinsic radical defect (IRD) state with an absorption band extending beyond 780 nm. Via experimental and theoretical investigations, we reveal that the radical‐related singly occupied molecular orbital (SOMO) level facilitates exciton dissociation and diffusion from π‐conjugated domains to IRD domains with an efficient charge transfer process. This process yields efficient second near‐infrared (NIR‐II) photoluminescence with a quantum yield of 1.8%. Leveraging this property, the GQDs facilitate high‐resolution NIR‐II fluorescence imaging of vessels, tumors, and lymph nodes in mice. This discovery boosts the applications of carbon‐based radicals in photonic technologies.
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BibTeX
@article{xu2026engineering,
title = {{Engineering Ultrastable Intrinsic Radicals: Graphene Quantum Dots With NIR‐II Emission for Dynamic Deep‐Tissue Bioimaging}},
author = {Qin Xu and Yijie Hou and Bingzhe Wang and Tesen Zhang and Yupeng Liu and Shuaiqi Li and Maohua Chen and Guichuan Xing and Dongbo Guo and Songnan Qu},
journal = {Advanced Science},
year = {2026},
month = aug,
doi = {10.1002/advs.76970},
url = {https://doi.org/10.1002/advs.76970},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Engineering Ultrastable Intrinsic Radicals: Graphene Quantum Dots With NIR‐II Emission for Dynamic Deep‐Tissue Bioimaging
AU - Qin Xu
AU - Yijie Hou
AU - Bingzhe Wang
AU - Tesen Zhang
AU - Yupeng Liu
AU - Shuaiqi Li
AU - Maohua Chen
AU - Guichuan Xing
AU - Dongbo Guo
AU - Songnan Qu
PY - 2026
DA - 2026/08/03
JO - Advanced Science
DO - 10.1002/advs.76970
UR - https://doi.org/10.1002/advs.76970
AB - Stable radicals in carbon‐based materials have witnessed great consideration in the field of photonic and quantum information technologies, yet their development has been hindered by inherent instability arising from high reactivity. Here, we demonstrate the stabilization of intrinsic radicals within graphene quantum dots (GQDs) synthesized via two‐dimensional polymerization of perylene derivatives. Numerous radicals are stably localized at periodically arranged lattice defects in bilayer graphene‐like plates, where the induced structural distortions and intralayer oscillations minimize interlayer interactions, thus enabling exceptional radical stability across a broad temperature range (100–500 K). This configuration generates an intrinsic radical defect (IRD) state with an absorption band extending beyond 780 nm. Via experimental and theoretical investigations, we reveal that the radical‐related singly occupied molecular orbital (SOMO) level facilitates exciton dissociation and diffusion from π‐conjugated domains to IRD domains with an efficient charge transfer process. This process yields efficient second near‐infrared (NIR‐II) photoluminescence with a quantum yield of 1.8%. Leveraging this property, the GQDs facilitate high‐resolution NIR‐II fluorescence imaging of vessels, tumors, and lymph nodes in mice. This discovery boosts the applications of carbon‐based radicals in photonic technologies.
SN - 2198-3844
ER -