Materials Today Communications
·
2021
·
IF 3.383
Guangzhi Jin,Yonglai Lu,Peng Yu,Liqun Zhang
Carbon dots (CDs) have attracted increasing attention as fluorescent agents for elastomer composites. Bottom-up synthesis of carbon dots (CDs) from molecular precursors would inevitably produce crude carbon dots (CCDs), i.e., a mixture of CDs, quasi CDs, polymer clusters, and molecular fluorophores. The CCDs are normally subjected to purification processes to obtain the pure CDs, while the purification procedures are time-consuming, expensive, and difficult to be scale-up. Herein, we directly used the CCDs as the fluorescent agents for silicon rubber. To achieve a good CCDs dispersion within the polymer matrix , we firstly prepared the CCDs fluid by mixing the CCDs solid with water, then the CCDs fluid was melt-mixed with the SiR (with the silica as filler) by a two-roll mill. The results revealed that small amounts of CCDs (less than 1 phr) could endow the matrix with intriguing luminescent property. Overall, this work offers a green and facile strategy to use CCDs as low-cost fluorescent agents for the SiR through melt-milling of CCDs fluid and rubber, which can be extended to a variety of other melt-processable polymer matrices (such as millable polyurethane rubber) and enables a broad range of potential applications.
研究领域:
材料科学
·
高分子化学
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DOI
高影响因子
RSC Advances
·
2019
·Vol. 9
·期 19
·10645-10650
·
IF 3.049
Tianhao Ji,Peidong Fan,Xueli Li,Zhipeng Mei,Yongyun Mao,Yanqing Tian
EDTA-bonded multi-connected carbon-dots (EDTA–C-dots) were prepared from carbon dot precursors and complexed with Eu3+ to give Eu3+-coordinated EDTA-bonded multi-connected carbon dots (Eu–EDTA–C-dots). Whereas EDTA–C-dots were readily soluble in DMSO, Eu–EDTA–C-dots could not be easily dissolved in DMSO, water, or other common organic solvents. The newly prepared materials were thoroughly characterized. The X-ray diffraction results showed that no crystalline phase of Eu oxides (europium oxide or europium hydroxide) could be observed in Eu–EDTA–C-dots. The infrared and UV-Vis spectra showed that coordination with Eu3+ ions did not damage the structure of the EDTA–C-dots. It was found that EDTA could be easily grafted on the surface of carbon dots and EDTA had minimal influence on the photoluminescence of the carbon dot matrix. In contrast, the existence of Eu3+ ions strongly quenched the photoluminescence of Eu–EDTA–C-dots. The measured and fitted decay lifetime indicated that Eu–EDTA–C-dots possessed two photoluminescence decay processes, i.e., radiative recombination and non-radiative recombination.
研究领域:
材料科学
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光学
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DOI
PubMed
高影响因子
Materials Chemistry Frontiers
·
2022
·Vol. 6
·期 19
·2859-2868
·
IF 8.683
Ming Liu,Ran Cen,Ji-Hong Lu,Tie-Hong Meng,Chun-Rong Li,Carl Redshaw,Timothy J. Prior,Zhu Tao,Xin Xiao
Fluorescent nitrogen and fluorine doped carbon dots (CDs) were prepared by a hydrothermal method using levofloxacin (LVFX) and cucurbit[6]uril (Q[6]) as the nitrogen and carbon sources, respectively. Decomposition of LVFX occurred at elevated temperature affording N,N′-desethylene levofloxacin hydrochloride (N,N′-DLH). The crystal structure of the resulting inclusion complex N,N′-DLH@Q[6]·[CdCl4]2(H3O)·9H2O was determined, where N,N′-DLH is protonated on each of the terminal nitrogens and the quinone functionality is a quinol which forms an intramolecular hydrogen bond to the carboxylic acid. The synthesized N,N′-DLH containing Q[6]-CDs emitted intense blue fluorescence with high photostability and exhibited stability at high ionic strength. In particular, the original rigid macrocyclic skeletons of these hosts were retained during the fabrication process, which helps in uniquely distinguishing them from other reported CDs. Meanwhile, the performance of the Q[6]-CDs was characterized using fluorescence and NMR spectroscopies. Subsequently, using the obtained Q[6]-CDs, an efficient sensing method for L-tryptophan (L-Trp) and capecitabine (CAP) has been developed based on macrocyclic host–guest chemistry. Under applicable conditions, the detection limits for L-Trp and CAP were calculated to be 5.13 × 10−8 M and 1.48 × 10−8 M, respectively.
研究领域:
分析化学
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材料科学
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药物化学
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DOI
高影响因子
Small
·
2024
·
IF 13
Xue Ou,Xinrui Chen,Siyu Zhao,Yarong Shi,Junhua Zhang,Min Wu,Arthur J. Ragauskas,Xueping Song,Zhanying Zhang
Carbon dots (CDs) have a wide light absorption range, which are promising candidates for photocatalytic water splitting H 2 evolution, but they show low activity for hydrogen evolution reaction (HER) due to the slow transfer efficiencies of photogenerated carriers. The electron cloud density of photocatalyst is essential for the separation and migration of photogenerated carriers. In this study, the effect mechanism of electron cloud density regulated by the substituents with different electronic effects on the photocatalytic HER of glucose-based CDs is clarified. CDs-SO 3 H and CDs-OH are first obtained by introducing electron-drawing group (─SO 3 H) and electron-donating group (─OH) using a tailoring post-processing strategy. Experimental results show that the H 2 yield catalyzed by CDs-SO 3 H is 89.95 µmol•g −1 in 4 h, which is about four times that of CDs, and 7.4 times that of CDs-OH. The ─SO 3 H induces a much negative energy band and high electron cloud density on CDs edges, promoting the separation and transfer of photogenerated carriers; while the CDs-OH exhibits a high positive charge density and an upward energy band, hindering the surface complexation of electron-hole pairs and HER. This study will provide an insight into the design of CDs catalysts with efficient photocatalytic HER at a molecular level.
研究领域:
材料科学
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光催化
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产品关联
DOI
PubMed
高影响因子
Advanced Materials Interfaces
·
2021
·Vol. 9
·期 4
·2101633
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IF 6.147
Yi Cai,Minghao Wang,Mengxian Liu,Jing Zhang,Yong Zhao
An optical fiber sensing platform based on the nitrogen-doped carbon dots (N-CDs) for online detection of pH value in real time has been developed. The pH-sensitive N-CDs are synthesized by a one-pot hydrothermal method. To compose the sensing probe, the N-CDs are immobilized on the surface of the fiber tip by the biocompatible hydrogel. According to the results of optical simulation, the fiber tip is designed to be tapered for efficient excitation and fluorescence collection. The assembling process of the sensing probe can be accomplished by the method of in-situ polymerization without any mold in seconds. The fluorescence of the sensing probe can be enhanced or quenched by pH value variation in a certain range and transmits to the spectrometer. The maximum diameter of the proposed sensing probe is only 450 µ m. Therefore, the sensing platform with rapid response has great potential application for remote monitoring in the narrow space. Besides, the proposed platform is portable and provides a new photonic-sensing method for emergency analysis.
研究领域:
化学传感器
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生物医学工程
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2022
·
IF 16.744
Linjia Li,Rui Zhang,Yanhong Lin,Dejun Wang,Tengfeng Xie
The exploitation of morphological engineering strategies enables the design of semiconductor-based photocatalysts with a precision that significantly enhances their photocatalytic activity. In this study, a paradigm has been provided that embeds plasmonic nanostructures within the bulk of the semiconductor, which demonstrates an improvement in interfacial charge transfer and separation. It involves a distinct core-double shelled Au@carbon dots@CdS hybrid, exhibiting excellent photocatalytic H 2 generation under the visible light radiation. The interfacial engineering between the plasmonic nucleus and the semiconductor shell has been performed by the incorporation of carbon dots as faster charge channels. The effective driving force for plasmon-enhanced bulk charge separation of semiconductors and the unhindered interfacial charge transmission derived from carbon dots have been demonstrated by the use of steady state surface photovoltage (SPV) and transient state surface photovoltage (TPV) methods, as well as some intrinsic kinetics information of interfacial photoexcited charge carriers transfer processes.
研究领域:
材料科学
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光催化
·
纳米技术
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产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2020
·
IF 7.489
Gongxi Qiao,Gui Chen,Qin Wen,Wanqiang Liu,Jinwei Gao,Zhiqiang Yu,Qianming Wang
The commercial production of carbon dots will be concerned with the simplicity and energy consumption. Herein, maleic acid and m-phenylenediamine form elegantly simple sources for carbon dots. The two precursors are dissolved in formamid (abbreviated as FA) or N, N -dimethylformamide (abbreviated as DMF) and the dehydration-condensation processes have been performed at 30 min or 120 min under room temperature. No external energy/irradiations, reactants or high temperature will be required and the afforded carbon dots (abbreviated as CDs) are collected by extraction, centrifugation, dialysis and column chromatography. It has been found for the first time the choice of organic solvents has been correlated with emission color. The blue-emitting CDs (abbreviated as B-CDs) and green-emitting CDs (abbreviated as G-CDs) are yielded in FA and DMF respectively. Facts support that the increase of –CONH- units causes red-shift in emissions. The optical sensing of tetracycline has been explored and the detection limit of blue-emitting CDs is as low as 25 nM. Live cells exposed to B-CDs and G-CDs (0.5 mg/ml) show no apparent changes via both Cell Counting Kit-8 and Annexin V/7-AAD analysis. The blue and green fluorescent signals can be easily tracked in cells. It has been demonstrated that the two carbon dots can be fabricated as multiple-color light-emitting diodes (abbreviated as LEDs).
研究领域:
材料科学
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化学
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纳米技术
·
光学
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生物医学工程
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF NANOBIOTECHNOLOGY
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2014
·Vol. 12
·期 1
·1-12
·
IF 4.078
Wang Qing,Zhang Chunlei,Shen Guangxia,Liu Huiyang,Fu Hualin,Cui Daxiang
Background Fluorescent carbon dots (Cdots) have attracted increasing attention due to their potential applications in sensing, catalysis, and biomedicine. Currently, intensive research has been concentrated on the synthesis and imaging-guided therapy of these benign photoluminescent materials. Meanwhile, Cdots have been explored as nonviral vector for nucleic acid or drug delivery by chemical modification on purpose.Results We have developed a microwave assisted one-step synthesis of Cdots with citric acid as carbon source and tryptophan (Trp) as both nitrogen source and passivation agent. The Cdots with uniform size show superior water solubility, excellent biocompatibility, and high quantum yield. Afterwards, the PEI (polyethylenimine)-adsorbed Cdots nanoparticles (Cdots@PEI) were applied to deliver Survivin siRNA into human gastric cancer cell line MGC-803. The results have confirmed the nanocarrier exhibited excellent biocompatibility and a significant increase in cellular delivery of siRNA, inducing efficient knockdown for Survivin protein to 6.1%. In addition, PEI@Cdots complexes mediated Survivin silencing, the arrested cell cycle progression in G1 phase as well as cell apoptosis was observed.Conclusion The Cdots-based and PEI-adsorbed complexes both as imaging agents and siRNA nanocarriers have been developed for Survivin siRNA delivery. And the results indicate that Cdots-based nanocarriers could be utilized in a broad range of siRNA delivery systems for cancer therapy.
研究领域:
纳米技术
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生物医学
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癌症治疗
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分子生物学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF NANOBIOTECHNOLOGY
·
2021
·Vol. 19
·期 1
·1-14
·
IF 10.435
Wang Yuhui,Xie Zhuomi,Wang Xiuhua,Peng Xin,Zheng Jianping
Background Fluorescent carbon-dots (CDs) with multifaceted advantages have provided hope for improvement of crop growth. Near infrared (NIR) CDs would be more competitive and promising than short-wavelength emissive CDs, which are not directly utilized by chloroplast. The molecular targets and underlying mechanism of these stimulative effects are rarely mentioned. Results NIR-CDs with good mono-dispersity and hydrophily were easily prepared by a one-step microwave-assisted carbonization manner, which showed obvious UV absorptive and far-red emissive properties. The chloroplast-CDs complexes could accelerate the electron transfer from photosystem II (PS II) to photosystem I (PS I). NIR-CDs exhibited a concentration-dependent promotion effect on N. benthamiana growth by strengthening photosynthesis. We firstly demonstrated that potential mechanisms behind the photosynthesis-stimulating activity might be related to up-regulated expression of the photosynthesis and chloroplast synthesis related genes, among which PsbP and PsiK genes are the key regulators. Conclusion These results illustrated that NIR-CDs showed great potential in the applications to increase crop yields through ultraviolet light harvesting and elevated photosynthesis efficiency. This work would provide a theoretical basis for the understanding and applications of the luminescent nanomaterials (not limited to CDs) in the sunlight conversion-related sustainable agriculture. Graphic abstract
研究领域:
农业
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植物生理学
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分子生物学
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纳米材料科学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF LUMINESCENCE
·
2022
·
IF 4.171
Xiaolin Tian,Zhefeng Fan
Rare earth-carbon dots (RE-CDs) nanomaterials combine the merits of both RE and CDs, which have been the promising candidates in the biochemical sensing field. Owing to the diversity of synthetic methods and precursors, the electronic structure, optical properties and sensing performances of RE-CDs vary greatly. Nevertheless, a comparing study focusing on the synthetic methods of RE-CDs using same precursors has not been reported to date. To facilitate the exploration of the interaction mechanisms for RE–CDs, same precursors (folic acid and terbium nitrate) were used to synthesize RE-CDs via two most common fabrication methodologies (doping and direct coordination) in this study. The morphologies, surface groups, and optical properties of the as-prepared terbium-doped CDs (Tb-CDs) and terbium functionalized CDs (Tb@CDs) were comprehensively compared and analyzed. The anthrax biomarker (dipicolinic acid, DPA) sensing performances of both RE-CDs were also evaluated. Taking the original CDs without terbium as control, the Tb-CDs had higher quantum yield (QY) and longer fluorescence lifetime , and the fluorescence emission peak was red-shifted, suggesting the effective passivation of surface defects . On the contrary, QY and fluorescence lifetime of Tb@CDs decreased, and the emission peak remained unchanged, indicating that interaction between free Tb 3+ and CDs led to the less excited electrons, similar to the fluorescence quenching behavior of metal ions on CDs. Further characterization also helped in demonstrating the different interaction mechanisms. Moreover, for the superior performance in DPA detection, Tb-CDs was chosen as the probe for the follow-up application. The Tb-CDs exhibited a sensitive response to DPA in the concentration range of 0.05–8 μM with the detection limit of 44 nM. In addition, it was successfully applied to real samples of running water and lake water.
研究领域:
纳米材料科学
·
生物传感技术
·
光化学
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产品关联
DOI
高影响因子
CHINESE JOURNAL OF POLYMER SCIENCE
·
2025
·
IF 4
Zhou Xiao-Xia,Yin Yi-Ting,Zhang Xiao-Yi,Li Shu-Sheng,Jiang Xu-Bao,Zhu Xiao-Li,Kong Xiang-Zheng
Fluorescent polyurea-carbon dots (PU-CD) were successfully achieved through a co-pyrolysis technique, combining polyurea (PU) with carboxyl-containing carbon dots (PCD) at a temperature of 220 °C. The PU was fabricated via a simple precipitation polymerization process using toluene diisocyanate in a water/acetone binary solvent system. PCD was generated by thermal treatment of poly(ethylene glycol) (PEG) at the same elevated temperature. To elucidate the structural characteristics of PU-CD, as well as its precursor components PU and PCD, a comprehensive suite of analytical techniques was employed, including transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), dynamic light scattering (DLS) and X-ray photoelectron spectroscopy (XPS). These analyses confirmed the formation of amide bonds resulting from the reaction between the terminal amines of PU and the carboxyl groups of PCD. An in-depth comparison of the fluorescence properties of PU-CD revealed marked enhancements in fluorescence intensity when contrasted with PU, PEG, and the individual PCD. The research explored the impact of various factors such as concentration, pH in aqueous solutions, and solvent type on the fluorescence emission of these materials, providing valuable insights into their emission mechanisms. It was particularly noteworthy that both PCD and PU-CD exhibited a confined-domain crosslink-enhanced emission effect. Utilizing the aqueous dispersion of PU-CD as a fluorescent probe, the detection of doxycycline (DOX), a long-acting, broad-spectrum, semi-synthetic tetracycline antibiotic, was achieved with a detection limit of 2.9×10 −7 mol/L. This study introduces a simple, green, and cost-effective fluorescent probe for the detection of DOX, which has significant potential for application in the realms of analytical chemistry and food safety monitoring in the future.
研究领域:
分析化学
·
材料科学
·
纳米技术
·
传感器
·
环境监测
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产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2018
·
IF 5.091
Bisang Chen,Feiming Li,Liling Zou,Dejian Chen
Hydrogen bonding interactions guided supramolecular self-assembly has been widely studied, which played important roles in the field of nanotechnology and nanodevices. Herein, an effective intermolecular hydrogen bonding mediated heating-up synthesis of high-quality fluorescent carbon dots (CDs) is developed based on hydrogen-bonding between trimesic acid and urea. Upon optimizing the hydrogen-bonding interaction, high quality of CDs with high monodispersity and stability could be obtained. Besides, these CDs could be used for sensitive and specific detection of ferric ions. The novel strategy may pave a new way in molecular engineering for the fabrication of high quality of CDs.
研究领域:
纳米技术
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）