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The near-infrared light (NIR) absorption of nitrogen-doped graphene quantum dots (NGQDs) containing different N-doping sites is systematically investigated with density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations with Perdew-Burke-Ernzerhof (PBE) functionals. The results show that the ultra-small HOMO-LUMO gaps (0.3-1.0 eV) of various N-doping structures (graphitic, amino, and pyridinic at center, and graphitic at edge) are attributed to the spin-polarization of the energy states, which effectively enhances the NIR absorption for NGQDs. Overall, the graphitic N-doping structure exhibits the best NIR absorption. Moreover, the electron attraction effect of the different N-sites is found to be crucial for the LUMO level, where stronger electron attraction lowers the LUMO energy. This work provides critical insight in further design of NGQDs for NIR absorption.
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http://dx.doi.org/10.1039/d1cp04572e | DOI Listing |
J Org Chem
September 2025
School of Chemical and Biopharmaceutical Sciences, Technological University Dublin, City Campus, Grangegorman, Dublin D07 EWV4, Ireland.
A series of unsymmetrically substituted BODIPY dyes featuring fused benzo- or naphtho-fragments on one pyrrolic unit were synthesized from the corresponding pyrrolic precursors. The synthetic route was optimized using a modular approach based on the condensation of formylpyrroles with alkylpyrroles, enabling the identification of precursor combinations that minimize byproduct formation and improve preparative yields. The resulting benzo- and naphtho-fused BODIPYs display intense fluorescence in the red region, with emission maxima spanning 590-680 nm and fluorescence quantum yields ranging from 0.
View Article and Find Full Text PDFLuminescence
September 2025
Department of Physics, Saveetha Engineering College (Autonomous), Chennai, Tamilnadu, India.
The iron nickel magnesium tetra-oxide (FeNiMgO) nanocomposites (NCs) first reported in this article were synthesized using the sol-gel method. For investigation using powder X-ray diffraction (PXRD), the presence of a cubic structure is confirmed. In Raman spectroscopy, the vibrational modes are investigated.
View Article and Find Full Text PDFJ Am Chem Soc
September 2025
Nanochemistry Department, Max Planck Institute for Solid State Research, Heisenbergstraße 1, 70569 Stuttgart, Germany.
Covalent organic frameworks (COFs) have been emerging as versatile reticular materials due to their tunable structures and functionalities, enabled by precise molecular engineering at the atomic level. While the integration of multiple components into COFs has substantially expanded their structural complexity, the strategic engineering of diverse functionalities within a single framework the random distribution of linkers with varying lengths remains largely unexplored. Here, we report a series of highly crystalline mixed-length multivariate COFs synthesized using azobenzene and bipyridine as linkers, where tuning the ratio of linkers and incorporating palladium effectively modulates the balance between near-infrared (NIR) light absorption and catalytic sites for NIR-generation of hydrogen peroxide (HO).
View Article and Find Full Text PDFNatl Sci Rev
August 2025
Center for AIE Research, Shenzhen Key Laboratory of Polymer Science and Technology, Guangdong Provincial Key Laboratory of New Energy Materials Service Safety, College of Material Science and Engineering, Shenzhen University, Shenzhen 518060, China.
Multimodal phototheranostics has been recognized as one of the most momentous advances in cancer treatment. Of particular interest is a single molecular species simultaneously featuring in multiple imaging and synergistic phototherapies; the development of such a molecular species is nevertheless a formidably challenging task. Herein, we innovatively designed and synthesized three aggregation-induced emission (AIE)-active molecules with emission in the second near-infrared (NIR-II) window, by employing 10-indeno[1,2-][1,2,5]thiadiazolo[3,4-]quinoxalin-10-one as the electron acceptor, 4-(-butyl)--(4-(-butyl)phenyl)--phenylaniline as the electron donor, and different π-bridge moieties.
View Article and Find Full Text PDFJ Mater Chem B
September 2025
State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, College of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China.
Adenosine triphosphate (ATP) is a critical biomolecule in cellular energy metabolism, with abnormal levels in the bloodstream linked to pathological conditions such as ischemia, cancer, and inflammatory disorders. Accurate and real-time detection of ATP is essential for early diagnosis and disease monitoring. However, conventional biochemical assays and other techniques suffer from limitations, including invasive sample collection, time-consuming procedures, and the inability to provide dynamic, monitoring.
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