ACS Applied Electronic Materials
·
2020
·
IF 0
Qiang Xu,Xiang Wang,Hang Zhang,Wenyi Shao,Jing Nie,Yong Guo,Juan Wang,Xiaoping Ouyang
A high Z CsPbBr3 halide perovskite with large charge carrier diffusion length was used for radiation detection applications. The high sensitivity X-ray detector is expected to be used for imaging applications. The free-seeding CsPbBr3 single crystals (SCs) were directly grown on ITO glass. We fabricated the Ag/CsPbBr3/ITO sandwich structural X-ray detector with Schottky contact at room temperature. We investigated the X-ray detection and phase-contrast X-ray imaging of the all-inorganic halide perovskite CsPbBr3 SCs. The devices exhibit high performances with low dark current density (∼5–27 nA/cm2) and high sensitivity (770 μC·Gy–1·cm–2) with an applied voltage of 8 V. An “L”-shape imaging was obtained based on the CsPbBr3 SC X-ray detector array, which makes it a promising application for pixel X-ray imaging techniques.
研究领域:
材料科学
·
辐射探测
·
成像技术
·
半导体物理
✓ 已验证
产品关联
DOI
JOURNAL OF LUMINESCENCE
·
2024
·
IF 3.3
Kuo Shen,Ruiting Zhang,Yahong Jin,Yanmei Li,Yihua Hu
X-ray storage phosphors are found wide-ranging applications in medical diagnosis, nondestructive testing and X-ray imaging. However, designing X-ray storage phosphors with high electron storage capacity still poses a daunting challenge. In this study, we designed a fluorescent powder based on Eu 2+ -doped BaSiO 3 , demonstrating excellent optical information storage characteristic. Under high-energy X-ray filling, shallow traps exhibit low electron capacity and only produce weak afterglow, which greatly helps to minimize the impact of afterglow on the image quality during X-ray imaging. In addition, the deep traps at 1.01 eV filled with high-energy X-ray allow the material to store information for a long time. The crystal structure, photoluminescence (PL) and thermoluminescence (TL) spectra were studied systematically. The electron trapping properties of the material were analyzed using TL spectroscopy. Finally, we fabricated a flexible film with phosphors, the flexible film has been utilized to demonstrate high-quality real-time X-ray imaging and achieve time-delayed X-ray imaging of curved objects, such as flexible circuit boards.
研究领域:
材料科学
·
医学成像
·
放射学
✓ 已验证
DOI
高影响因子
Nanoscale
·
2019
·Vol. 11
·期 13
·6182-6191
·
IF 6.97
Jinjin Ma,Qianting Yao,John A. McLeod,Lo-Yueh Chang,Chih-Wen Pao,Jiatang Chen,Tsun-Kong Sham,Lijia Liu
Inorganic lead halide perovskite CsPbX3 (X = Cl, Br, or I) nanocrystals are promising candidate materials for light-emitting devices and optoelectronics. Mn-Doped CsPbX3 is of particular interest, as the Mn-doping introduces an additional emission band, making this material a promising white-light emitter. In this study, Mn-doped CsPb(Br/Cl)3 nanocrystals are prepared at room-temperature and ambient pressure. The chemical environment of Mn, and the luminescence of these nanocrystals are analyzed in detail using X-ray diffraction (XRD), extended X-ray absorption fine structure (EXAFS), X-ray absorption near-edge structure (XANES) and X-ray excited optical luminescence (XEOL). Although the introduction of Mn does not alter the long-range order of the CsPbX3 crystal, it leads to a local lattice contraction with the bond length of Mn–X much shorter than Pb–X. We also find excitation energy-dependence in both the intensity and wavelength of the perovskite excitonic emission band, while only in intensity of the Mn emission band. Detailed fitting of the XEOL reveals that the perovskite emission band is dual-channel, and it is the excitation energy-dependent intensity variation of these two channels that drives the observed red-shift of the combined emission band. Our findings also confirm that the Mn emission band is driven by exciton-Mn energy transfer and clarify the Mn chemical environment and the luminescence mechanism in Mn-doped CsPb(Br/Cl)3 nanocrystals.
研究领域:
材料科学
·
光电子学
·
纳米技术
·
固体物理
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry C
·
2024
·
IF 5.7
Zezhen Liu,Jingtao Zhao,Danyang Shen,Lei Lei,Shiqing Xu
Lanthanide-doped fluoride nanoparticles (NPs) exhibit tunable X-ray excited optical luminescence (XEOL) and X-ray excited persistent luminescence (XEPL) properties, demonstrating promising applications in X-ray imaging. However, the mechanisms underlying shell thickness-dependent variations in XEOL and XEPL intensities remain unclear. In this work, we utilize homogeneous NaYF4:Tb@NaYF4 and heterogeneous NaYF4:Tb@NaLuF4 core/shell NPs to investigate the role of shell thickness. Our results reveal an optimal shell thickness of approximately 3 nm for both XEOL and XEPL, which contrasts with behaviors observed in upconversion systems. The shell layer effectively passivates NP surface defects, reducing energy migration from activators to these defects. However, it also absorbs input X-ray photons, which can diminish X-ray absorption in the core layer. Our findings contribute to the design of lanthanide-doped core/shell NPs with enhanced XEOL and XEPL performances.
研究领域:
材料科学
·
纳米技术
·
光学
·
放射学
✓ 已验证
产品关联
DOI
高影响因子
Advanced Optical Materials
·
2023
·Vol. 12
·期 11
·2302434
·
IF 9
Zhi-Zhong Zhang,Zi-Lin He,Jian-Bin Luo,Jun-Hua Wei,Xiu-Xian Guo,Jing-Hua Chen,Dai-Bin Kuang
The current mainstream planar X-ray imaging techniques face significant challenges for accurately capturing the internal structure of curved objects, since the variable distances between the curved objects and the flat-panel scintillation screen cannot eliminate the distortion in X-ray imaging. Though large-area and transparent curved scintillation screens are much more desirable. Here, organic–inorganic hybrid Mn-based single crystals ([CH 3 Ph 3 P] 2 MnX 4 , X = Cl, Br, I) exhibiting high photoluminescence quantum yield (PLQY) and low melting temperature have been employed to prepare transparent glass for X-ray scintillation imaging application through a low-temperature melting strategy. The [CH 3 Ph 3 P] 2 MnBr 4 -glass shows high PLQY (47.8%), high-resolution X-ray imaging performance (12.3 lp mm −1 ), low limit of detection (25.33 nGy s −1 ), and impressive X-ray irradiation stability (102 Gy). Furthermore, high-contrast X-ray imaging at a low dose (6.865 µGy per exposure, 14.5 times lower than the chest radiograph) is achieved. Based on the low glass transition temperature ( T g = 53.6 °C) and easy-shapeable properties of [CH 3 Ph 3 P] 2 MnBr 4 -glass scintillator, the large-area curved scintillation screen with a series of sizes of Φ 2×4 – Φ 8×4 cm 2 can be easily fabricated and show high X-ray imaging quality. These findings provide a paradigm for future research in shapeable X-ray scintillators, unlocking new possibilities for curved and 3D X-ray imaging.
研究领域:
材料科学
·
光学
·
放射学
·
成像技术
✓ 已验证
DOI
高影响因子
Flexible and Printed Electronics
·
2021
·Vol. 6
·期 1
·015008
·
IF 3.588
Li Xiang,Ya Wang,Xiyuan Liu,Xuekai Huang,Zhilong Xin,Yangbing Xu,Chuan Liu,Kai Wang,Jun Chen,Yang Yang,Shengdong Zhang,Hang Zhou
X-ray photodetection are frequently used in medical diagnoses industrial inspection and environmental radiation detection. Currently, there is an ongoing effort to develop bendable or flexible x-ray photodetectors (PDs) to meet the demand on light weight and arbitrary shape detection system. Here, a highly bendable indirect x-ray PD is designed by coupling a P3HT:PC61BM organic photodetectors (OPDs) with a flexible perovskite quantum dots (QDs) embedded polymer scintillator. The flexible perovskite QDs scintillator exhibits high radioluminescence with emission peak centers at the 537 nm, which falls in maximum absorption range of poly(3-hexylthiophene) (P3HT). The OPD, with 2\,\mu {\text{m }}active layer, exhibits low dark currents in the range of tens of nanoampere per square centimeter over a wide reversed biased range. The OPD demonstrates detectable light signal down to {\text{0}}{\text{.1}}\,\mu {\text{W}}\,{\text{cm}}{{\text{ }}^{ - 2}} and low dose detection capability. The coupling of perovskite QDs scintillator and OPD shows a sensitivity of 638 e nGy−1 mm−2 \left( {{\text{10}}{\text{.2 }}\mu {\text{C G}}{{\text{y}}^{ - {\text{1}}}}{\text{ c}}{{\text{m}}^{ - {\text{2}}}}} \right) at a dose rate of 1 mGy s−1, which brings the possibilities of realizing highly bendable x-ray PDs.
研究领域:
材料科学
·
医学影像
·
辐射检测
✓ 已验证
DOI
高影响因子
JOURNAL OF NANOPARTICLE RESEARCH
·
2017
·Vol. 19
·期 8
·1-7
·
IF 2.02
Li Nannan,Liu Jian,Duan Xiulan,Yu Fapeng,Jiang Huaidong
This report discusses the preparation and microstructure of Co/Ni co-doped MgGa 2 O 4 nanoparticles. The nanoparticles with the size of 20–55 nm were synthesized by sol-gel method. The phase and crystallinity were confirmed by X-ray powder diffraction (XRD) pattern. The particle size was estimated according to XRD data and transmission electron microscopy. The electronic structure was studied using X-ray photoelectron spectroscopy (XPS). The XPS studies showed that Ga 3+ ions possess tetrahedral and octahedral sites of spinel structure and the inverse degree (two times of the fraction of tetrahedral Ga 3+ ions) has increased with the increase of the doping concentration of Co 2+ and Ni 2+ ions. For Co/Ni co-doped MgGa 2 O 4 , two broad absorption bands of 350~500 and 550~700 nm were observed in the absorption spectra. The broad band at 350~500 nm was assigned to the combination of the absorption of octahedral Co 2+ and Ni 2+ ions, whereas the absorption band at 550~700 nm is mainly due to tetrahedrally coordinated Co 2+ ions and octahedrally coordinated Ni 2+ ions.
研究领域:
材料科学
·
纳米技术
✓ 已验证
DOI
高影响因子
Minerals
·
2023
·Vol. 13
·期 3
·387
·
IF 2.5
Min Zhang,Fangfang Chen,Guoying Yan,Hongjing Li,Jing Li,Guan Peng,Hongdong Yu
The characteristics of Baiyun Obo niobium-bearing minerals are complex physicochemical properties that make the beneficiation of niobium minerals extremely difficult. In this paper, X-ray diffraction, X-ray fluorescence and mineral liberation analyzer (MLA) systems were used to study the niobium occurrence state and distribution of niobium-bearing minerals in the samples from Baiyun Obo. The results show that the chemical and mineral compositions of the sample are complex, with a Nb2O5grading of 0.24%. There are many kinds of niobium minerals, including ilmenorutile, nioboaeschynite-Nd, baotite, latrappite, euxenite-Y, fergusonite and columbite-Mn, and the highest mass fraction of 0.55% is achieved with Nb in nioboaeschynite-Nd, followed by the mass fraction of ilmenorutile (0.33%). All of the niobium-containing minerals demonstrate a low degree of dissociation. Flotation experiments explored the optimal flotation conditions for HOBA (1-hydroxyoctyl-1,1-bisphosphonic acid) as a flotation collector for Baiyun Obo niobium minerals, which is able to increase the grade of Nb2O5in the concentrate to 1.31%. The optimal use conditions of the reagent are pH 3.5–4.5, and the amount of the collector is 1000 g/t. By further optimizing the beneficiation process and reagent system, ilmenorutile and nioboaeschynite-Nd were significantly enriched in the concentrate, which suggested that HOBA can efficiently increase the grade of Nb2O5in the concentrate.Keywords:MLA;distribution regularity;flotation;niobium;Baiyun Obo
研究领域:
矿物加工
·
地球化学
·
材料科学
✓ 已验证
DOI
高影响因子
Nanoscale
·
2023
·Vol. 15
·期 33
·13628-13634
·
IF 6.7
Sijian Wu,Lifang Yuan,Geng Chen,Chaoyue Peng,Yahong Jin
All-inorganic metal halide perovskite (MHP) materials have been widely studied because of their unique optoelectronic properties, whereas there has been little research reported on their X-ray afterglow imaging properties. Herein, we report the design and synthesis of Mn2+-doped hexagonal CsCdCl3 MHP crystals with excellent X-ray scintillation and X-ray induced afterglow. The orange emission from Mn2+ shows a red shift due to the strong interaction of the Mn2+–Mn2+ dimers formed at higher doping concentrations. The high-energy X-rays with higher electron filling capacity to feed the shallow (0.71 eV) and deep (0.90–1.08 eV) traps enable a long orange afterglow for more than 300 min. The afterglow emission can be rejuvenated effectively by 870 nm stimulus or heating even after 72 h of decay. Finally, we demonstrate the proof-of-concept applications of the fabricated flexible scintillator films for real-time online X-ray imaging with a spatial resolution of 12.2 lp mm−1, as well as time-lapse X-ray imaging recorded by a cell phone, which shows promise for being able to do offline late-time detection of X-ray afterglow imaging in the future.
研究领域:
材料科学
·
光电学
·
放射学
·
成像科学
✓ 已验证
DOI
高影响因子
CHEMICAL RESEARCH IN CHINESE UNIVERSITIES
·
2017
·Vol. 33
·期 3
·415-421
·
IF 1.024
Zhao Yongsheng,Li Qin,Ren Hejun,Zhou Rui
Magnetic MnFe 2 O 4 -bentonite was synthesized by chemical co-precipitation method(CCM) and applied as catalyst in heterogeneous activation of persulfate(PS) to oxidize a target pollutant, 2,4-dichlorophenol(2,4-DCP), in aqueous solutions. The surface morphology and structure of MnFe 2 O 4 -bentonite were characterized by X-ray diffraction( XRD), scanning electron microscope(SEM), energy dispersive X-ray(EDX) and X-ray photoelectron spectroscopy(XPS) analyses.The catalytic activity of MnFe 2 O 4 -bentonite for 2,4-DCP degradation was evaluated considering the effects of various process parameters, such as mass ratio of MnFe 2 O 4 to bentonite, concentration of catalyst, PS concentration, and pH. The MnFe 2 O 4 -bentonite hybrid exhibited higher catalytic activity than pure MnFe 2 O 4 . Treatment with 5 g/L MnFe 2 O 4 -bentonite at 30 °C for 240 min oxidized 92% of 100 mg/L 2,4-DCP(70.2% mineralization), whereas treatment with pure MnFe 2 O 4 under the same condition oxidized only 70% of the pollutant. This result indicate the enhanced performance of the activated PS. Moreover, MnFe 2 O 4 -bentonite exhibits stable performance with minimal loss in activity after five successive runs. Thus, MnFe 2 O 4 -bentonite could be a promising catalyst in oxidative degradation of 2,4-DCP.
研究领域:
环境科学
·
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2023
·Vol. 16
·期 3
·1147
·
IF 3.4
Peng Qiao,Yiheng Ping,Hongping Ma,Lei Lei
Inorganic scintillators are of great significance in the fields of medical CT, high-energy physics and industrial nondestructive testing. In this work, we confirm that the Pb4Lu3F17: Re (Re = Tb, Eu, Sm, Dy, Ho) crystals are promising candidates for a new kind of scintillator. Detailed crystal structure information is obtained by the Rietveld refinement analysis. Upon X-ray irradiation, all these scintillators exhibited characteristic 4f-4f transitions. The Ce and Gd ions were verified to be useful for enhancing the scintillation intensity via introducing energy transfer processes. The integrated scintillation intensity of the Pb4Lu3F17: Tb/Ce is about 16.8% of the commercial CsI (Tl) single crystal. Our results manifested that Pb4Lu3F17: Re has potential application in X-ray detection and imaging.Keywords:Pb4Lu3F17;X-ray;rare earth;CsI (TI);energy transfer
研究领域:
材料科学
·
医学成像
·
核物理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CARBOHYDRATE POLYMERS
·
2015
·
IF 4.074
Linbin Jiang,Yuan Lu,Xingyun Liu,Hu Tu,Jianwei Zhang,Xiaowen Shi,Hongbing Deng,Yumin Du
Quaternized carboxymethyl chitosan (QCM-chitosan) and organic rectorite (OREC) immobilized nanofibrous mats are fabricated via layer-by-layer (LBL) technique in a self-assembly manner. The negatively charged cellulose nanofibrous mats hydrolyzed from electrospun cellulose acetate (CEL) mats are alternately modified with the positively charged QCM-chitosan and OREC intercalated composites and the negatively charged sodium alginate (ALG) via LBL technique. The morphology and antibacterial activity of the resultant mats are studied by changing the number of deposition bilayers, the compositions of dipping solutions and outermost layer. X-ray photoelectron spectroscopy results imply that QCM-chitosan and OREC are coated on cellulose mats. Besides, wide angle X-ray diffraction and small angle X-ray diffraction are applied to investigate the crystalline of the composite mats and the interlayer distance of OREC, respectively. The antibacterial activity of the mats increases with the incorporation of OREC into LBL films.
研究领域:
材料科学
·
纳米技术
·
高分子科学
·
表面工程
·
生物医学工程
·
抗菌技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）