APPLIED RADIATION AND ISOTOPES
·
2024
·
IF 1.6
Yue Li,Yongqiang Zhang,Guoqiang Zhong,Wenjing Pu,Wei Lu,Weihua Wang
Liquid scintillator consists of an organic solvent and one or more scintillation solutes, which can emit light pulses after absorbing X- and γ-rays, or high-energy particles. It has the characteristics of strong neutron/γ-ray (n/γ) discrimination, short decay time, unlimited size and low cost, which plays an important role in high-sensitivity and large-scale radiation detection, especially in the construction and safe operation of nuclear facilities. However, the impact of solvent selection and moisture content on the fluorescence-scintillation properties of scintillators has not been adequately investigated in the literature. In this study, liquid scintillators consisting of scintillation solutes, 2, 5-diphenyl-oxazole and 1, 4-bis (5-phenyl-2-oxazolyl) benzene, were prepared with different moisture contents, which were determined using the Karl-Fischer method. The fluorescence emission spectra, scintillation sensitivity and n/γ discrimination were systematically characterized using various solvents with corresponding moisture contents. The results show that the scintillation count rate and n/γ discrimination reach their maximum values when employing p -xylene as the solvent and maintaining moisture content below 20 ppm. The theoretical calculation elucidates the performance degradation of liquid scintillators induced by moisture.
研究领域:
核物理
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辐射探测
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ADVANCED MATERIALS
·
2023
·
IF 29.4
Wei Fu,Jiefu Yin,Huaqiang Cao,Zhongfu Zhou,Junying Zhang,Jingjing Fu,Jamie H. Warner,Cheng Wang,Xiaofang Jia,G. Neville Greaves,Anthony K. Cheetham
Photoluminescence blinking behavior from single quantum dots under steady illumination is an important but controversial topic. Its occurrence has impeded the use of single quantum dots in bioimaging. Different mechanisms have been proposed to account for it, although controversial, the most important of which is the non-radiative Auger recombination mechanism whereby photocharging of quantum dots can lead to the blinking phenomenon. Here, the singly charged trion, which maintains photon emission, including radiative recombination and non-radiative Auger recombination, leads to fluorescence non-blinking which is observed in photocharged single graphene quantum dots (GQDs). This phenomenon can be explained in terms of different energy levels in the GQDs, caused by various oxygen-containing functional groups in the single GQDs. The suppressed blinking is due to the filling of trap sites owing to a Coulomb blockade. These results provide a profound understanding of the special optical properties of GQDs, affording a reference for further in-depth research.
研究领域:
纳米材料
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光学
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材料科学
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生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
POLYMER
·
2023
·
IF 4.6
Wenjing Pu,Yue Li,Wei Lu,Bo Shi,Pengyu Tao,Lingling Huang
Radiation detection plays a crucial role in the construction and safe operation of nuclear facilities. Liquid scintillator is widely used in this field but its fluorescence-scintillation properties still require improvement to achieve high sensitivity detection at present. In this paper, a new liquid scintillator system is developed, which selects polysilane as the matrix, and aryl with electron repulsing/withdrawing groups as the grafting substituents. The conjugated structure between the Si–Si chain and the aryl scintillating group enables electron delocalization transfer, resulting in improved fluorescence emission spectra and scintillation sensitivity. Three aryl-grafted polysilanes with typical electron repulsing and withdrawing group are successfully synthesized by Grignard routes. The optical properties of the materials are evaluated through both molecular simulation and experimental measurements, to determine the electronic effect of aryl groups on the electron delocalization in modified polysilane scintillators. The scintillation count performance is also evaluated. In conclusion, polysilanes grafted with aryl groups can be utilized as a new type of liquid scintillator, and electron repulsing substituents could enhance the fluorescence-scintillation properties more effectively, which providing meaningful guidance for the further optimization of liquid scintillation composition .
研究领域:
辐射检测
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核设施
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材料科学
·
化学
·
物理学
✓ 已验证
DOI
高影响因子
DALTON TRANSACTIONS
·
2018
·Vol. 47
·期 16
·5670-5678
·
IF 4.099
Xiao Chen,Daqin Chen,Junni Li,Gaoliang Fang,Hongchao Sheng,Jiasong Zhong
As a novel type of promising materials, metal halide perovskites are a rising star in the field of optoelectronics. On this basis, a new frontier of zero-dimensional perovskite-related Cs4PbBr6 with bright green emission and high stability has attracted an enormous amount of attention, even though its photoluminescence still requires to clarification. Herein, the controllable phase transformation between three-dimensional CsPbBr3 and zero-dimensional Cs4PbBr6 is easily achieved in a facile ligand-assisted supersaturated recrystallization synthesis procedure via tuning the amount of surfactants, and their unique optical properties are investigated and compared in detail. Both Cs4PbBr6 and CsPbBr3 produce remarkably intense green luminescence with quantum yields up to 45% and 80%, respectively; however, significantly different emitting behaviors are observed. The fluorescence lifetime of Cs4PbBr6 is much longer than that of CsPbBr3, and photo-blinking is easily detected in the Cs4PbBr6 product, proving that the zero-dimensional Cs4PbBr6 is indeed a highly luminescent perovskite-related material. Additionally, for the first time, tunable emissions over the visible-light spectral region are demonstrated to be achievable via halogen composition modulations in the Cs4PbX6 (X = Cl, Br, I) samples. Our study brings a simple method for the phase control of CsPbBr3/Cs4PbBr6 and demonstrates the intrinsic luminescence nature of the zero-dimensional perovskite-related Cs4PbX6 products.
研究领域:
材料科学
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光电子学
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纳米技术
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光子学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nanoscale
·
2022
·Vol. 14
·期 17
·6392-6401
·
IF 8.307
Zhaoyan Yang,Yuhui Dong,Shenfei Zong,Lang Li,Kuo Yang,Zhuyuan Wang,Haibo Zeng,Yiping Cui
Single-molecule localization microscopy (SMLM) is one of the most promising super-resolution imaging techniques for visualizing ultrasmall cellular structures. Here, water-dispersed perovskite CsPbBr3 nanocrystals (CsPbBr3 NCs) fabricated by a one-step mechanochemical method are explored as a SMLM fluorophore for bioimaging. Due to their ultrahigh photoluminescence quantum yield (PLQY), inherent frequent fluorescence blinking, proper duty cycle and long-term photostability, an extremely high location precision of ∼3 nm was achieved, a sixfold enhancement than those reported previously. In addition, the spatial resolution of a SMLM image depends on the size of CsPbBr3 NCs, which is approximately 23 nm. Two closely spaced CsPbBr3 NCs with a gap of 40 nm can be clearly distinguished in the SMLM image. More importantly, unlike most perovskite quantum dots (QDs), one-step mechanochemically prepared CsPbBr3 NCs can retain their excellent fluorescence characteristics even after surface biofunctionalization, greatly reducing the current limitations of perovskite QDs on bioimaging. As an example, cell-derived exosomes (30–150 nm in diameter) labeled with CsPbBr3 NCs were easily identified by SMLM. In addition, after being functionalized with biotin, targeted SMLM imaging of the nuclear lamina or cell membranes of cells was achieved with an enhanced resolution. This work may open up a promising avenue to expand the field of perovskite QD-based SMLM to bioimaging with a high location accuracy.
研究领域:
材料科学
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纳米技术
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生物医学工程
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光学
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细胞生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
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