- 标题
- 摘要
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- 实验方案
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S, N-codoped Oil-soluble Fluorescent Carbon Dots for High Color-rendering WLED
摘要： Carbon dots (CDs) have attracted widespread attention in light-emitting-diode (LED) applications owing to their environmental friendliness, easy processing and unique optical properties. For the practical use of CDs in LEDs, the controllable synthesis of high performance oil-soluble carbon dots are still in urgent demand. In this study, S, N-codoped oil-soluble carbon dots (S, N-OCDs) with average size of 3.38 nm were prepared by solvothermal reaction of acetone, dimethyl trithiocarbonate (DMTTC) and nitric acid. Characterization results reveal that both the conjugated aromatic π systems from aldol condensation and highly active free radicals from DMTTC essentially dominate the development of this yellow-green emitting S, N-OCDs which possess high carbonization, quantum yield (21.08 %) and oil-solubility. Furthermore, a white light-emitting-diode (WLED) was fabricated through mixing the obtained S, N-OCDs and epoxy and drop-casting the mixure on the surface of gallium nitride (GaN) based blue chips. The as-prepared WLED showed excellent color rendering properties (CCT of 5389 K, CIE coordinates of (0.33,0.30), CRI of 88.38).
关键词： oil-soluble carbon dots,color rendering index,WLED,heteroatom doping
更新于2025-11-19 16:46:39
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Highly Photoluminescent and Stable N-Doped Carbon Dots as Nanoprobes for Hg2+ Detection
摘要： We developed a microreactor with porous copper fibers for synthesizing nitrogen-doped carbon dots (N-CDs) with a high stability and photoluminescence (PL) quantum yield (QY). By optimizing synthesis conditions, including the reaction temperature, flow rate, ethylenediamine dosage, and porosity of copper fibers, the N-CDs with a high PL QY of 73% were achieved. The PL QY of N-CDs was two times higher with copper fibers than without. The interrelations between the copper fibers with different porosities and the N-CDs were investigated using X-ray photoelectron spectroscopy (XPS) and Fourier Transform infrared spectroscopy (FTIR). The results demonstrate that the elemental contents and surface functional groups of N-CDs are significantly influenced by the porosity of copper fibers. The N-CDs can be used to effectively and selectively detect Hg2+ ions with a good linear response in the 0~50 μM Hg2+ ions concentration range, and the lowest limit of detection (LOD) is 2.54 nM, suggesting that the N-CDs have great potential for applications in the fields of environmental and hazard detection. Further studies reveal that the different d orbital energy levels of Hg2+ compared to those of other metal ions can affect the efficiency of electron transfer and thereby result in their different response in fluorescence quenching towards N-CDs.
关键词： carbon dots,microreactor,Hg2+ detection,porous copper fibers
更新于2025-11-19 16:46:39
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Synthesis of non-doped and non-modified carbon dots with high quantum yield and crystallinity by one-pot hydrothermal method using a single carbon source and used for ClO? detection
摘要： A facile and straightforward strategy was used to prepare carbon dots (CDs) using catechol as carbon source in one-pot hydrothermal method. The synthesis method is simple without any doping and modification and the prepared CDs do not require any post-processing. Characterizations of the obtained CDs indicated that they had high crystallinity and higher quantum yield (QY, 32%) than most non-functionalized and non-doped CDs. Noticeably, the fluorescence of CDs could be quenched with hypochlorite (ClO?) by oxidation of the residual pyrocatechol groups on the surface to o-benzoquinone exhibiting high sensitivity and selectivity for ClO? assay covered a linear range from 0.1 to 10 μM with a low detection limit of 30 nM. The results showed that the CDs provided a promising potential tool for the detection of ClO? in real water samples.
关键词： Quenching,Fluorescence,Hypochlorite,Carbon dots
更新于2025-11-19 16:46:39
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Multifunctional N,S co-doped carbon dots for sensitive probing of temperature, ferric ion, and methotrexate
摘要： In this paper, we have presented a facile method to fabricate nitrogen and sulfur co-doped carbon dots (N,S-CDs) for blood methotrexate (MTX) sensing applications. The N,S-CDs with quantum yield up to 75% were obtained by one-step hydrothermal carbonization, using reduced glutathione and citric acid as the precursors. With this approach, the formation and the surface passivation of N,S-CDs were carried out simultaneously, resulting in intrinsic fluorescence emission. Owing to their pronounced temperature dependence of the fluorescence emission spectra, resultant N,S-CDs can work as versatile nanothermometry devices by taking advantage of the temperature sensitivity of their emission intensity. In addition, the obtained N,S-CDs facilitated high selectivity detection of Fe3+ ions with a detection limit as low as 0.31 μM and a wide linear range from 3.33 to 99.90 μM. More importantly, the added MTX selectively led to the fluorescence quenching of the N,S-CDs. Such fluorescence responses were used for well quantifying MTX in the range of 2.93 to 117.40 μM, and the detection limit was down to 0.95 μM. Due to Binert^ surface, the N,S-CDs well resisted the interferences from various biomolecules and exhibited excellent selectivity. The proposed sensing system was successfully used for the assay of MTX in human plasma. Due to simplicity, sensitivity, selectivity, and low cost, it exhibits great promise as a practical platform for MTX sensing in biological samples.
关键词： Hydrothermal carbonization,Doped carbon dots,Excitation-independent emission,Multifunctional probe,Methotrexate,Surface passivation
更新于2025-11-19 16:46:39
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Enhanced removal and detection of benzo[a]pyrene in environmental water samples using carbon dots-modified magnetic nanocomposites
摘要： Magnetic nanoparticles (MNPs) have already proven their e?cacy in the disposal of a wide array of environmental contaminants in recent years. However, the di?culties in dispersibility and agglomeration of MNPs arising from its own physical and chemical properties limit its large-scale application. Herein, we fabricated the carbon dots/fatty acid-coated MNPs (CDs/C11-Fe3O4) through a facile and simple method. To utilize the advantage of carbon dots, these limitations can be mitigated by diminishing the size of MNPs and modifying the surface of MNPs. Detailed characterization including VSM, FT-IR, XPS and TEM conformed that the higher adsorption capacity of CDs/C11-Fe3O4 is mainly attributed to low average size (< 8 nm), which is obviously lower than that of C11-Fe3O4 (about 13 nm). The CDs/C11-Fe3O4 showed higher adsorption performance than that of C11-Fe3O4 nanocomposites (76.23 ng mg?1 for CDs/C11-Fe3O4 and 59.89 ng mg?1 for C11-Fe3O4). The adsorption processes of BaP on both C11-Fe3O4 and CDs/C11-Fe3O4 nanocomposites are exothermic, and well simulated by pseudo-second-order model. Moreover, the CDs/C11-Fe3O4 were also applied for the detection of BaP in large-volume water samples, which satis?es the China environmental protection standard, are promising candidates for water remediation.
关键词： Magnetic nanocomposites,Carbon dots,Hydrophilicity,Adsorption,Benzo[a]pyrene
更新于2025-11-14 17:15:25
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Facile microwave synthesis of carbon dots powder with enhanced solid-state fluorescence and its applications in rapid fingerprints detection and white-light-emitting diodes
摘要： In this report, we successfully developed a simple and fast MW-assisted method for preparing CDs with strong solid-state fluorescence (SSF) by using phthalic acid and piperazine as precursors. The prepared p-CDs can be obtained in high yield (48.7%) and emit bright yellow-green SSF under 365 nm UV light. The absolute PL quantum yield (PLQY) of p-CDs in solid state was measured to be 20.5%, which is much higher than that in aqueous solution. This interesting phenomenon shows that p-CDs not only successfully conquer the aggregation-caused fluorescence quenching (ACQ) effect, but also achieve enhanced fluorescence emission, which was rarely reported in previous literatures as CDs in solid state always reduce their fluorescence emission due to the excessive resonance energy transfer (RET) or direct π-π interactions. In addition, the relationship between the feed ratio of precursors and optical properties of the CDs were also investigated detailedly. Based on their strong SSF, the p-CDs were successfully used in rapid latent fingerprints detection and white light-emitting diodes (WLEDs) preparation with high quality. In summary, this research not only developed a new type of CDs with strong enhanced SSF, but also offered a valuable reference for design SSF-emitting CDs with high yield.
关键词： Carbon dots,Solid-state fluorescence,Light-emitting diodes,Latent fingerprints
更新于2025-11-14 17:04:02
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Development of a fluorescence immunoassay for highly sensitive detection of amantadine using the nanoassembly of carbon dots and MnO2 nanosheets as the signal probe
摘要： Fluorescence immunoassays are rapid, convenient and cost-effective for the sensitive quantitation of chemical contaminants in foodstuff. In this study, a competitive fluorescence ELISA was developed for the sensitive detection of amantadine (AMD) based on the alkaline phosphatase (ALP)-triggered fluorescence "turn-on" signals. As a fluorescence substrate, carbon dots (CDs) were adsorbed onto the surface of the MnO2 nanosheets (NSs) and formed a nanoassembly of p-CDs@MnO2 NSs which results in the fluorescence quench of CDs. The ALP labelled on antibody could catalyze the hydrolysis of the 2-phospho-L-ascorbic acid into ascorbic acid. The latter could then reduce and decompose the MnO2 NSs, which was accompanied by the release of CDs from the surface of MnO2 NSs and led to the fluorescence recovery of CDs. The change of the fluorescence intensity is related to the concentration of AMD in solution and thus could be applied to detect AMD in an ALP-based ELISA system. The fluorescent ELISA showed a linear detection for AMD in the range of 0.048 ng mL?1 to 1.1 ng mL?1 with a detection limit (LOD) of 0.035 ng mL?1. The novel fluorescent ELISA shows potential for the highly sensitive detection of AMD and other analytes in food analysis.
关键词： manganese dioxide nanosheets,carbon dots,fluorescent immunoassay,amantadine
更新于2025-11-14 17:04:02
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Carbon dots synthesized at room temperature for detection of tetracycline hydrochloride
摘要： The traditional synthesis methods of carbon dots (CDs) have some disadvantages of complicated operation and a large amount of energy consumption. To address these limitations, we synthesized yellow-green luminescent CDs at room temperature according to the principle of amine-aldehyde condensation in this work. This reaction is simple, economical, energy saving and is extremely consistent with the concept of green synthesis and sustainable development. In addition, studies have found that tetracycline hydrochloride (TC) can quench the fluorescence of the as-prepared CDs through Inner filter effect (IFE). The changes of the fluorescence intensity also have a good linear relationship with the concentration of TC in the range of 10.0-400.0 μM, and the detection limit is 6.0 μM. This method has been successfully used to determine the tetracycline content of tetracycline tablets. Finally, the interaction mechanism between TC and CDs was analyzed and discussed.
关键词： room temperature synthesis,tetracycline,carbon dots
更新于2025-11-14 17:03:37
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2,4,6-Trinitrophenol detection by a new portable sensing gadget using carbon dots as a fluorescent probe
摘要： An optical sensing gadget using fluorescence of carbon dots (CDs) was developed to realize the in-field detection of 2,4,6-trinitrophenol (TNP) in tap water and lake water samples. Fluorescent CDs were prepared through a one-step hydrothermal synthetic route. The fluorescence spectra demonstrated that the CDs could specifically discriminate TNP from other nitroaromatic explosives in an aqueous medium. The fluorescence of the CDs was quenched linearly with the concentration of TNP in the range from 1 to 100 μM, with a detection limit of 0.48 μM (3σ/k). The detection mechanism was ascribed to the synergistic effect of the inner filter effect and electron transfer. In addition, a portable sensing gadget based on a high-precision RGB color sensor and a micro control unit was developed. With use of the sensing gadget and the CDs, TNP detection in tap water and lake water samples was realized. Importantly, the portable sensing gadget combined with highly stable, low-toxicity, and sensitive CDs might have great potential for application in extensive in-field sensing situations.
关键词： 2,4,6-Trinitrophenol detection,Portable sensing gadget,Carbon dots,Fluorescence analysis
更新于2025-11-14 17:03:37
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A magnetofluorescent boron-doped carbon dots as a metal-free bimodal probe
摘要： High-resolution observation of biological process is vital for biological researches and diagnosing diseases, which requires accurate diagnosis that involves coordinating imaging technologies such as fluorescence and magnetic resonance (MR). Nowadays, metal-based labels have been used for dual modality imaging. However, heavy metal ions are not environment-and organism-friendly. Therefore, it is a desirable to fabricate a metal-free label with fluorescence and MR properties. Herein, we synthesized boron–doped carbon dots (B–CDs) with dual modal properties through a one-pot solvothermal process. Compared with boron-free CDs, B–CDs exhibited apparent red-shift, higher fluorescence intensity, and higher longitudinal relaxivity (r1 = 5.13 mM-1 s-1). It demonstrated that boron doping can enhance the fluorescence intensity of CDs, and maybe lead to form paramagnetic centers. The fluorescence and MR imaging of B–CDs make them a prospective label for clinical applications as a result of their oversimplified synthesis process, low cost, good biocompatibility and low toxicity. It will open a new window for building novel imaging labels.
关键词： Boron,Magnetic resonance,Fluorescence,Carbon dots
更新于2025-11-14 17:03:37