MOLECULES
·
2023
·Vol. 28
·期 4
·1632
·
IF 4.6
Guozhu Ren,Danyang Zhang,Hao Wang,Xiaofang Li,Ruiping Deng,Shihong Zhou,Long Tian,Liang Zhou
The luminescent performances of near-infrared (NIR) lanthanide (Ln) complexes were restricted greatly by vibration quenching of X-H (X = C, N, O) oscillators, which are usually contained in ligands and solvents. Encapsulating Ln3+into a cavity of coordination atoms is a feasible method of alleviating this quenching effect. In this work, a novel ytterbium complex [Yb(DPPDA)2](DIPEA) coordinated with 4,7-diphenyl-1,10-phenanthroline-2,9-dicarboxylic acid (DPPDA) was synthesized and characterized by FT-IR, ESI-MS and elemental analysis. Under the excitation of 335 nm light, [Yb(DPPDA)2](DIPEA) showed two emission peaks at 975 and 1011 nm, respectively, which were assigned to the characteristic2F5/2→2F7/2transition of Yb3+. Meanwhile, this ytterbium complex exhibited a plausible absolute quantum yield of 0.46% and a luminescent lifetime of 105 μs in CD3OD solution. In particular, its intrinsic quantum yield was calculated to be 12.5%, and this considerably high value was attributed to the near-zero solvent molecules bound to Yb3+and the absence of X-H oscillators in the first coordination sphere. Based on experimental results, we further proposed that the sensitized luminescence of [Yb(DPPDA)2](DIPEA) occurred via an internal redox mechanism instead of an energy transfer process.Keywords:ytterbium complex;near-infrared luminescence;absolute quantum yield;luminescent lifetime;intrinsic quantum yield;internal redox mechanism
研究领域:
无机化学
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材料科学
·
光学材料
✓ 已验证
产品关联
DOI
PubMed
高影响因子
OPTICAL MATERIALS
·
2022
·
IF 3.754
Shaofeng Liang,Muqun Wang,Wei Gao,Xia Zhao
Hydrothermal methods are commonly used to synthesize carbon dots (CDs), but the synthesized CDs have the disadvantage of low quantum yields. In this paper, we used acid treatment, elemental doping, and passivation to treat the CDs, which could increase the quantum yield from 36% to 42%, 61% and 68%, respectively, and the doping and passivation treatments resulted in red-shifted and blue-shifted emission behavior of the CDs. The optical properties , morphology and chemical structure of CDs are analyzed to investigate the reasons for the quantum yield increase and the mechanism of excitation dependent emission (EDE) and excitation independent emission (EIE). The increase of quantum yield is mainly due to the increase of pyridine N content. The different optical behaviors depend mainly on the surface states of CDs. C–OH and C–O–C can create new energy levels leading to the appearance of EDE properties. C=O is an electron-absorbing group that weakens the conjugation effect leading to blue shift.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry C
·
2018
·Vol. 6
·期 47
·13013-13022
·
IF 5.976
Dong Lu,Yiping Tang,Jinwei Gao,Qianming Wang
In contrast to conventional nanomaterials or organic dyes, carbon dots possess a variety of appealing properties including chemical inertness and easy manipulation and they can be dispersed in water. Herein, the use of a concentrated solar irradiation sintering strategy for the rapid and efficient assembly of carbon dots (CDs) has been reported for the first time. This novel alternative pathway effectively uses a renewable source and the process is feasible and environmentally sustainable. Three kinds of CDs were obtained, which demonstrate blue, green and red luminescence. Highly efficient blue-emitting CDs with quantum yield as high as 81% have been realized. The blue and red carbon dots give rise to excitation-independent emission peaks at 443 and 592 nm, respectively; however, the green CDs feature a continuous shift and the evolution of emission curves varies from 480 to 538 nm. By regulating the composition and ratios of these tri-color carbon dots, the emission band generates peaks from blue to red light, which cover almost the entire visible light range. Upon a single ultra-violet excitation at 365 nm, a white-light emission with CIE coordinates of (0.28, 0.33) was detected and the signal was very close to pure white light (0.33, 0.33). This study introduces a new method for fabricating low-cost nanoparticles as potential phosphors for light-emitting uses.
研究领域:
材料科学
·
环境科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2024
·
IF 2.7
Yulong Cui,Wenxuan Sun,Yao Dong,Yingnan Jiang,Jie Zhang,Tong Zhao,Jing Zhang,Yankai Wang,Meiling Sun,Guangchao Yin
The afterglow material based on carbon dots (CDs), with boric acid (BA) serving as the matrix, demonstrates outstanding structural rigidity. The covalent bond structure is particularly advantageous for stabilizing the triplet states of CDs, thus shielding the triplet excitons from quenching. Urea, on the other hand, harbors numerous CO and –NH2 functional groups, fostering the creation of hydrogen bond structures with CDs. This impedes the non-radiative recombination of CDs, thereby enhancing the production of afterglow. Here, we blend two substrate materials with distinct structural characteristics, utilizing their combined effect on restricting CDs. By employing this method, we have successfully synthesized afterglow materials with an exceptional absolute quantum yield (QY) of 61.22% and an afterglow delay time surpassing 5 s. Urea is employed to modulate the size and graphitization degree of CDs, thereby adjusting the emission wavelength in both solid state fluorescence (S-FL) and afterglow within composite materials. Furthermore, by adjusting the mixed ratio of BA and urea, thus altering their respective proportions in interacting with CDs, the brightness of S-FL and the delay time of afterglow are adjusted.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2019
·Vol. 11
·期 13
·5998-6003
·
IF 6.97
Dongjun Shen,Yijuan Long,Jie Wang,Yuanyuan Yu,Jiangli Pi,Lili Yang,Huzhi Zheng
A reduction pathway was developed to tune the fluorescence quantum yield (QY) and emission wavelength of carbon dots (CDs). Reducing the original CDs (QY ca. 1.55%, maximum emission ca. 520 nm) with NaBH4 increased QY to 7.25% and blue-shifted the maximum emission to 450 nm. Treating the original CDs with LiAlH4 increased QY to ca. 7.44% and blue-shifted the maximum emission to 345 nm. The distinct fluorescence characteristics of the original CDs, NaBH4-treated CDs, and LiAlH4-treated CDs were conferred by their differing surface groups. Moreover, the original CDs, NaBH4-treated CDs, and LiAlH4-treated CDs responded differently to a specific oxidizer of hydroxyl groups. The increase in the fluorescence QY and blue-shift of the emission wavelength were explained. This study provides a foundation for the preparation and tuning of CDs with excellent fluorescence performance, as well as for the development CD-based fluorescent probes.
研究领域:
材料科学
·
光学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
·
2023
·
IF 4.3
Shihua Liao,Xiang Long,Yanshun Ma,Shaogui Wu,Jiayang Wang
Multicolor fluorescent carbon dots (CDs) have wide application prospects in many fields. Presented herein reported a synthesis of multicolor fluorescent CDs using zanthoxylum bungeanum as a carbon precursor. By changing the nitrogen sources, blue, green, and red fluorescent carbon dots (B-CDs, G-CDs, and R-CDs) with stable optical properties and high quantum yields (QY) were synthesized. Their emission wavelengths are 492 nm, 523 nm, and 601 nm respectively and their QYs were measured to be 13.1%, 11.2%, and 9.8%, respectively. These CDs exhibit good salt resistance, photobleaching resistance, and chemical stability. These characteristics make them suitable for various applications, particularly in the field of anti-counterfeiting fluorescent ink. This study provides an economic and efficient strategy for synthesizing multicolor fluorescent CDs derived from natural products, highlighting the potential for producing multicolor CDs and enhancing their application value.
研究领域:
材料科学
·
化学
·
植物学
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2024
·
IF 5.6
Qiulian Liu,Weihua Li,Xiaolong Qiao,Haiguang Zhao
Colloidal carbon dots (C-dots) have excellent optical properties and they have been widely used for various types of applications. Compared to the C-dots prepared using chemicals, the Biomass-derived C-dots have attracted a great of attention because of their environmental friendliness and biocompatibility. However, currently obtained C-dots using biomass have low quantum yield. In this work, we demonstrated an efficient precursor of Magnolia flower for synthesizing high-quantum yield C-dots via hydrothermal approach. High performance liquid chromatography and Bradford assay were used to analyze the compositions of the Magnolia flower, which determine the quality of the C-dots. The typical emission bands of the as-prepared C-dots cover from 400 to 550 nm at different excitation wavelengths. The C-dots synthesized using violet Magnolia flower have the QY as high as 11.9%, which is higher than that of 10.4% (white Magnolia flower), because the violet color gives the higher content of the N. The as-obtained C-dots have excitation-dependent color and high quantum yield, showing a great potential for the use of the anti-counterfeiting system.
研究领域:
材料科学
·
植物学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2017
·
IF 2.686
Mingguang Zhu,Youzhen Zhuo,Hongyu Guo,Fafu Yang,Jiabin Qiu
The first perylene liquid crystals bearing six peripheral alkyl substituents on both 1,6,7,12-bay positions and imides positions were designed and synthesized in yields of 72–77%. The studies on their mesomorphic behaviors suggested that they possessed good ordered hexagonal columnar mesophase with low phase transition temperatures and wide ranges of mesophase temperature in comparison with their precursors with chloric groups and the similar perylene liquid crystal with 4- tert -butylphenolic groups on bay positions. Their photophysical properties revealed that they also had higher fluorescence intensities and fluorescence quantum yields than that of their precursors with chloric groups and the similar perylene liquid crystal with 4- tert -butylphenolic groups on bay positions. The good fluorescence in both solution and solid film were observed for the first time for perylene liquid crystals. This research indicated that the introduction of long p -nonylphenol units on bay position is an effect strategy to obtain perylene liquid crystal with good liquid crystalline behavior and excellent fluorescent property.
研究领域:
材料科学
·
化学
✓ 已验证
DOI
高影响因子
CRYSTENGCOMM
·
2023
·Vol. 25
·期 40
·5722-5729
·
IF 3.1
Abraham Mensah,Wei-Min Chen,Ennin Vendish Kweku,Peng-Lai Liu,Juan-Juan Shao,Fang-Ming Wang,Li-Zhuang Chen
Five novel ‘all-in-one’ (AIO) structured cuprous iodide coordination materials 1–5 are presented. With the introduction of planar aromatic groups on the ligand, 1,4-diazabicyclo[2.2.2]octane (DABCO), targeted at eliminating stronger π–π interactions through the twisted nature of the latter species, the complexes displayed good stability, solubility, and high quantum yields of emissions ranging from 70.3–95.3%. Further systematic studies were performed on the relationship between their luminescence and modification of the ligands with halogen atoms. This work provides a reasonable idea for designing luminescent cuprous iodide materials with high quantum yields of emission for use in solid-state lighting in the future.
研究领域:
无机化学
·
材料科学
·
光物理
✓ 已验证
DOI
高影响因子
Advanced Science
·
2024
·Vol. 11
·期 29
·2308523
·
IF 14.3
Zimin Yao,Xiaokun Wen,Xia Hong,Ran Tao,Feifei Yin,Shuo Cao,Jiayi Yan,Kexin Wang,Jiwei Wang
Constrained by a limited understanding of the structure and luminescence mechanisms of carbon dots (CDs), achieving precise enhancement of their photoluminescence (PL) performance without altering the emission wavelength and color remains a challenge. In this work, a deuterated CD is first achieved by simply replacing the reaction solvent from H 2 O to D 2 O. The substitution of D atoms for H atoms is not limited on the surface but also within the internal structure of CDs. Deuteration affects the formation of the π -conjugated network structure by altering the content of sp 2 carbon and sp 3 carbon, ultimately inducing a reconstruction for energy level structure of CDs. Both the intrinsic state and surface state emission, including quantum yield, emission intensity and lifetime, are significantly enhanced after deuteration. It benefits from the reduction in non-radiative transitions, since the lowered vibrational frequencies of D atoms and optimized local energy level distribution in CDs structure. The deuterated CDs are applied in the fabrication of white-light-emitting diodes to show their application potential. This work provides a highly versatile route for improving and controlling photoluminescence performance of CDs and has opportunities to guide the development of CDs for practical applications.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Omega
·
2024
·
IF 3.7
Shiqiang Hou,Ning Lin,Yi Wang
Red-emitting fluorescent carbon dots (CDs) have garnered significant attention due to their wide-ranging applications in biological fields. However, challenges such as complex precursors, labor-intensive preparation processes, and low quantum yields have hindered their broader utilization. In this study, we developed a simple and efficient solvothermal method to synthesize fluorescent CDs with tunable emission wavelengths using aniline derivatives as precursors. The emission wavelengths of the synthesized CDs were influenced by the functional groups at the para-position of the aniline derivatives with stronger electron-donating effects leading to a red shift in emissions. Notably, bright red-emitting CDs with a quantum yield of 19.42% and excellent photobleaching resistance were obtained by using p-phenylenediamine as the sole precursor. These CDs exhibited sensitivity to Fe3+ ions, demonstrating a strong linear detection range (R2 = 0.999) from 0 to 50 μM. Additionally, the CDs were uniform in size (2–5 nm), emitted stable red fluorescence in pH conditions ranging from 4 to 10, and were successfully internalized by glioma cells, enabling precise fluorescence imaging of gliomas both in vitro and in vivo.
研究领域:
生物医学工程
·
材料科学
·
肿瘤学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2024
·
IF 18.5
Yupeng Liu,Bingzhe Wang,Yunsen Zhang,Jia Guo,Xiaoyi Wu,Defang Ouyang,Shi Chen,Yeqing Chen,Shuangpeng Wang,Guichuan Xing,Zikang Tang,Songnan Qu
Carbon dots (CDs) are a burgeoning star of luminescent carbon-based nanomaterials with emerging interest for various applications. Luminescence from the sp 2 -conjugated domains in the carbon cores is considered to be the intrinsic bandgap emission of CDs, whereas the relationship between them remains poorly understood. Simultaneously, the solvent relaxation of water molecules will quench the fluorescence of CDs, thus, obtaining strong luminescence from CDs aqueous solutions remains a great challenge. Herein, a facile one-step spatial-confined cross-condensation method that uses a heat-induced self-foaming process in ambient pressure has been developed to synthesize highly luminescent CDs with unprecedented photoluminescence quantum yield (PLQY) over 97.2% in water. The unique precursor-derived cross-arranged perylene skeleton in the cores hinders π–π stacking, while the hydrophobicity of the conjugated units mitigates solvent relaxation by water molecules, resulting in near-unity PLQY in aqueous solutions, enabling this to demonstrate the first optically pumped green lasing emission in the CDs aqueous solution. Moreover, a biomaterial-based white light emitting diode is fabricated using the CDs-stained silks as a fluorescence conversion cover to realize a high luminous efficiency of 60.7 lm W −1 with CIE color coordinate of (0.33, 0.35).
研究领域:
材料科学
·
光学工程
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）