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Photoluminescence properties of Tm^(3+)/Tb^(3+)/Sm^(3+) tri-doped Na_(5)Y_(9)F_(32) single crystal with high thermal stability for white light-emitting diodes

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Journal of Rare Earths 2021年第5期39卷 512-519页

作者： Yang Qiao Xiong Zhou Jianli Zhang Haiping Xia Hongwei Song Baojiu Chen Key Laboratory of Photo-electronic Materials Ningbo UniversityNingbo 315211China State Key Laboratory on Integrated Optoelectronics College of Electronic Science and Engineering and College of PhysicsJilin UniversityChangchun 130012China Department of Physics Dalian Maritime UniversityDalian 116026China

A novel Tm^(3+)/Tb^(3+)/Sm^(3+)tri-doped Na_(5)Y_(9)F_(32)single crystal was synthesized by a modified Bridgman method for the propose of white light emitting diodes.The fluorescence spectra of various Sm^(3+)ion concentrations and fixed 0.4 mol%Tm^(3+)and 0.5 mol%Tb^(3+)were measured and studied systematically excited by near-ultraviolet light of 355 nm.The Sm3+ion concentration takes apparent effect on the relative intensity of peaks in the visible region and the color coordinate combining from these emission bands.A near pure white light emission with color coordinates(0.3295,0.3057)and color temperature(5657 K)can be obtained when the concentrations of Tm^(3+),Tb^(3+)and Sm^(3+)ions are 0.4 mol%,0.5 mol%and 0.8 mol%,respectively.Furthermore,the practical down-conversion internal quantum yield was measured by integrating spheres at about 14.39%.The tri-doped Na_(5)Y_(9)F_(32)single crystal shows a high thermal stability inferring from the temperature dependent emission in which the integrated emission intensities are reduced only by^3%with the increase of temperature from 280 to 450 K.The present results demonstrate that the Tm^(3+)/Tb^(3+)/Sm^(3+)tri-doped Na_(5)Y_(9)F_(32)single crystal may provide a promising candidate for white light-emitting diodes,luminescent materials and fluorescent display devices.

关键词： Na_(5)Y_(9)F_(32)single crystal Tm^(3+)/Tb^(3+)/Sm^(3+) Bridgman method White light emission Rare earths

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Effects of Bi^(3+) on down-/up-conversion luminescence,temperature sensing and optical transition properties of Bi^(3+)/Er^(3+)co-doped YNbO_(4) phosphors

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Journal of Rare Earths 2022年第3期40卷 381-389,I0001页

作者： Xin Wang Xiangping Li Hongquan Yu Sai Xu Jiashi Sun Lihong cheng Xizhen Zhang Jinsu Zhang Yongze Cao Baojiu Chen School of Science Dalian Maritime UniversityDalian 116026China

A series of YNbO_(4):Bi^(3+) and YNbO_(4):Bi^(3+)/Er^(3+) phosphors were prepared by a conventional high temperature solid-state reaction method.The results of XRD and Rietveld refinement confirm that monoclinic phase YNbO_(4)samples are achieved.The down-/up-conversion luminescence of Er^(3+) ions was investigated under the excitation of ultraviolet light(327 nm)and near infrared light(980 nm).Under 327 nm excitation,broad visible emission band from Bi^(3+) ions and characteristic green emission peaks from Er^(3+) ions are simultaneously observed,while only strong green emissions from Er^(3+) ions are detected upon excitation of 980 nm.Remarkable emission enhancement is observed in down-/up-conversion luminescence processes by introducing Bi^(3+) ions into Er^(3+)-doped YNbO_(4)phosphors.Pumped current versus up-conversion emission intensity study shows that two-photon processes are responsible for both the green and the red up-conversion emissions of Er^(3+)ion.Through the study of the temperature sensing property of Er^(3+) ion,it is affirmed that the temperature sensitivity is sensitive to the doping concentration of Bi^(3+) ions.By comparing the experimental values of the radiative transition rate ratio of the two green emission levels of Er^(3+) ions and the theoretical values calculated by Judd-Ofelt(J-O)theory,it is concluded that the temperature sensing property of Er^(3+) ions is greatly affected by the energy level splitting.

关键词： YNbO_(4):Bi^(3+)/Er^(3+) Down-conversion luminescence Up-conversion luminescence Temperature sensing Rare earths

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Growth and Optical Spectra of Tb^(3+)/Eu^(3+) Co-doped Cubic NaYF_4 Single Crystal for White Light Emitting Diode

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Journal of Materials Science & Technology 2015年第12期31卷 1232-1236页

作者： Yongzhang Jiang Haiping Xia Jiazhong Zhang Shuo Yang Haochuan Jiang Baojiu Chen Key Laboratory of Photoelectronic Materials Ningbo University Ningbo Institute of Materials Technology and Engineering Chinese Academy of Sciences Department of Physics Dalian Maritime University

High quality Tb^3＋/Eu^3＋ co-doped cubic NaYF 4 single crystal in the size of Φ1.0 cm×6.6 cm was grown by a modified Bridgman method using KF as assistant flux for NaF-YF 3 system under the condition of completely closed Pt crucible.A white light emission from the combination of the violet-blue,blue,green,orange,and red lights with chromaticity coordinates of x = 0.3107,y = 0.3274,correlated color temperature of T c = 6637 K,color rendering index of R a = 83,and color quality scale of Q a = 82 could be obtained from 1.51 mol%Tb^3＋ and 1.42 mol%Eu^3＋ co-doped cubic NaYF 4 single crystal when being excited by a 369 nm light.This indicates that Tb^3＋/Eu^3＋）co-doped cubic NaYF 4 single crystal has a potential application in white light emitting diode excited by ultraviolet light.

关键词： Cubic NaYF 4 single crystal KF flux Tb^3＋/Eu^3＋ ions White light emission

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Optical Spectra and Gain Properties of Ho^(3+)/Pr^(3+)Co-doped LiYF_4 Crystal

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Journal of Materials Science & Technology 2014年第9期30卷 910-916页

作者： Jiangtao Peng Haiping Xia Peiyuan Wang Haoyang Hu Lei Tang Yuepin Zhang Haochuan Jiang Baojiu Chen Key Laboratory of Photo-electronic Materials Ningbo University Ningbo Institute of Materials Technology & Engineering Chinese Academy of Sciences Department of Physics Dalian Maritime University

The LiYF4 single crystals singly doped Ho3＋ and co-doped Ho3＋, Pr3＋ ions were grown by a modified Bridgman method. The Judd-Ofelt strength parameters （Ω2, Ω4, Ω6） of No3＋ were calculated according to the absorption spectra and the Judd-Ofelt theory, by which the radiative transition probabilities （A）, fluorescence branching ratios （β） and radiative lifetime （τ rad） were obtained. The radiative lifetimes of 5/6 and 5/7 levels in Ho3＋（1 mol%）：LiYF4 are 10.89 and 20.19 ms, respectively, while 9.77 and 18.50 ms in Ho3＋/pr3＋ doped crystals. Hence, the τ rad of 5/7 level decreases significantly by introduction of Pr3＋ into Ho3＋：LiYF4 crystal which is beneficial to the emission of 2.9 μm. The maximum emission cross section of Ho3＋：LiYF4 crystal located at 2.05 μm calculated by McCumber theory is 0.51 ×10-20 cm2 which is compared with other crystals. The maximum emission cross section at 2948 nm in Ho3＋/pr3＋ co-doped LiYF4 crystal obtained by Fuchtbauer- Ladenburg theory is 0.68 × 10-20 cm2, and is larger than the value of 0.53 × 10-20 cm2 in Ho3＋ singly doped LiYF4 crystal. Based on the absorption and emission cross section spectra, the gain cross section spectra were calculated. In the Ho3- ions singly doped LiYF4 crystal, the gain cross sections for 2.05 μm infrared emission becomes positive once the population inversion level reaches 30%. It means that the pump threshold for obtaining 2.05 μm laser is probably lower which is an advantage for Ho3＋-doped LiYF4 2.05 μm infrared lasers. The calculated gain cross section for 2.9 μm mid-infrared emission does not become positive until the population inversion level reaches 40% in Ho3＋/pr3＋：LiYF4 crystal, but 50% in Ho3＋ singly doped LiYF4 crystal, indicating that a low pumping threshold is achieved for the H03＋：5/6 → 5/7 laser operation with the introduction of Pr3＋ ions. It was also demonstrated that Pr3＋ ion can deplete rapidly the lower laser Ho3＋：5/7 level and has influence on the Ho3＋：5/6 level. The Ho3＋/pr3＋：LiYF4 crystal may be a potential media for 2.9 μm mid-infr

关键词： LiYF4 crystal 2.9 μm Ho3/pr3＋ Optical spectra Gain cross section

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Near infrared emissions from both high efficient quantum cutting (173%) and nearly-pure-color upconversion in NaY(WO_(4))_(2):Er^(3+)/Yb^(3+) with thermal management capability for silicon-based solar cells

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Light(Science & Applications) 2024年第1期13卷 113-126页

作者： Duan Gao Baojiu Chen Xuezhu Sha Yuhang Zhang Xin chen Li Wang Xizhen Zhang Jinsu Zhang Yongze Cao Yichao Wang Lei Li Xiangping Li Sai Xu Hongquan Yu Lihong cheng School of Science Dalian Maritime UniversityDalian 116026 LiaoningChina

Raising photoelectric conversion efficiency and enhancing heat management are two critical concerns for siliconbased solar cells.In this work,efficient Yb^(3+) infrared emissions from both quantum cutting and upconversion were demonstrated by adjusting Er^(3+) and Yb^(3+) concentrations,and thermo-manage-applicable temperature sensing based on the luminescence intensity ratio of two super-low thermal quenching levels was discovered in an Er^(3+)/Yb^(3+) codoped tungstate system.The quantum cutting mechanism was clearly decrypted as a two-step energy transfer process from Er^(3+) to Yb^(3+).The two-step energy transfer efficiencies,the radiative and nonradiative transition rates of all interested 4 f levels of Er^(3+) in NaY(WO_(4))_(2) were confirmed in the framework of Föster-Dexter theory,Judd-Ofelt theory,and energy gap law,and based on these obtained efficiencies and rates the quantum cutting efficiency was furthermore determined to be as high as 173%in NaY(WO_(4))_(2):5 mol%Er^(3+)/50 mol%Yb^(3+) sample.Strong and nearly pure infrared upconversion emission of Yb3+under 1550 nm excitation was achieved in Er^(3+)/Yb^(3+)co-doped NaY(WO_(4))_(2) by adjusting Yb^(3+) doping concentrations.The Yb^(3+) induced infrared upconversion emission enhancement was attributed to the efficient energy transfer ^(4)I_(11/2)(Er^(3+))+^(2)F_(7/2)(Yb^(3+))→^(4)I_(15/2)(Er^(3+))+^(2)F_(5/2)(Yb^(3+))and large nonradiative relaxation rate of ^(4)I_(9/2).Analysis on the temperature sensing indicated that the NaY(WO_(4))_(2):Er^(3+)/Yb^(3+)serves well the solar cells as thermos-managing material.Moreover,it was confirmed that the fluorescence thermal quenching of ^(2)H_(11/2)/^(4)S_(3/2) was caused by the nonradiative relaxation of ^(4)S_(3/2).All the obtained results suggest that NaY(WO_(4))_(2):Er^(3+)/Yb^(3+) is an excellent material for silicon-based solar cells to improve photoelectric conversion efficiency and thermal management.

关键词： quantum thermal relaxation

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采用强电离放电法降解废水中难降解有机物

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高电压技术 2017年第8期43卷 2653-2659页

作者：白敏菂冷白羽陈宝玖大连海事大学物理系大连116026

为降解废水中难降解有机污染物,采用强电离放电将氧离解、电离成低温氧等离子体,并将其注入废水处理反应塔中,在反应塔中主要进行四步关键的等离子体反应。首先,低温氧等离子体中O_2^+与水分子反应生成微量·OH;然后,O_3与微量·OH反应... 详细信息

为降解废水中难降解有机污染物,采用强电离放电将氧离解、电离成低温氧等离子体,并将其注入废水处理反应塔中,在反应塔中主要进行四步关键的等离子体反应。首先,低温氧等离子体中O_2^+与水分子反应生成微量·OH;然后,O_3与微量·OH反应形成高反应速率常数的过氧羟基自由基引发剂HO_2·;接着,高浓度O_3在引发剂HO_2·作用下生成氧化力强、反应速率很高的足量高浓度·OH;因此·OH将无选择、快速地将废水中难降解有机污染物降解成无害小分子有机物,最终矿化成CO_2、H_2O。实验结果表明:低温氧等离子体仅用2.5 min把废水中难降解有机污染物质量浓度从145.0 mg/L降至25.5 mg/L,去除率达到83.5%。与常规污水处理技术相比,采用强电离放电形成低温氧等离子体降解废水中难降解有机物方法具有设备投资和运行成本低以及污水处理系统简单等特点,将为受难降解有机物污染的废水回用提供一种经济、实用的新方法。

关键词：低温氧等离子体深度降解难降解有机污染物废水强电离放电

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Value of Fiberoptic Ductoscopy in Diagnosing and Treating Multiporous Nipple Discharge

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Chinese Journal of Clinical Oncology 2008年第3期5卷 211-214页

作者： Lijin Wang Shaoshi Yang baojiu Xie Jie Gao Jianqiu chen Department of Surgery the 2nd Hospital ofTianjin Medical University Tianjin 300211China.

OBJECTIVE To explore the value of fiberoptic ductoscopy in diagnosing and treating bilateral and polyporous nipple discharge (ND).METHODS Fiberoptic ductoscopy was conducted in 29 patients with bilateral and polyporous ND.After the ductoscopy,the patients with intraductal papilloma (IDP) underwent a surgical procedure,and the others,identified with galactostasis,mammary duct ectasia (MDE) and obstructive galactophoritis (OG),received a ductoscopy-guided interventional therapy. RESULTS Among 29 cases,and with 79 galactophores examined,IDP was found in 11 cases (37.9% of the total cases),or 13.9% of the galactopores examined.IDP was found in 9 of 11 cases with a bloody nipple discharge,while IDP was seen in 2 of the 18 cases with a non-bloody nipple discharge.The excision accuracy achieved 100% in the cases,and postoperative pathological diagnosis accordance rate reached 88.9%. CONCLUSION Fiberoptic ductoscopy has many features such as ability to see the lesion,and accurate preoperative localization,thus eliminating excessive excision of tissue during surgery.For most patients with ND,especially those suffering galactostasis,OG or MDE,washout under fiberoptic ductoscopy and interventional therapy may achieve a thorough cure of the disease.

关键词：纤维乳管镜诊断治疗临床应用

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KLa(MoO_4)_2:Sm^(3+),Eu^(3+)荧光粉中能量传递研究

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稀有金属材料与工程 2015年第10期44卷 2476-2480页

作者：吴中立张艳秋陈宝玖大连海事大学辽宁大连116026 辽宁工业大学辽宁锦州121001

采用高温固相法合成了KLa0.7-x(MoO4)2:0.3Eu3+,xSm3+系列红色发射荧光粉,利用XRD对样品的晶体结构进行了分析,发现所得到的样品均为纯相。采用荧光光谱手段对样品的发光性质及能量传递进行了研究。在低Sm3+掺杂浓度时采用277及394 nm... 详细信息

采用高温固相法合成了KLa0.7-x(MoO4)2:0.3Eu3+,xSm3+系列红色发射荧光粉,利用XRD对样品的晶体结构进行了分析,发现所得到的样品均为纯相。采用荧光光谱手段对样品的发光性质及能量传递进行了研究。在低Sm3+掺杂浓度时采用277及394 nm激发样品,其发光强度几乎不随掺杂浓度变化,若利用404 nm激发样品发光随Sm3+浓度有明显增强;当Sm3+掺杂浓度较高时,利用277,394及404 nm激发观察到了Sm3+对Eu3+发光产生了猝灭作用。采用电多极相互作用模型及交换相互作用模型对Sm3+到Eu3+的能量传递过程的物理本质进行了探讨,确定了在低掺杂浓度下Sm3+到Eu3+的能量传递是基于交换相互作用的结果。通过对Eu3+的5D0能级荧光动力学过程的分析进一步证实了在低Sm3+掺杂浓度时Sm3+充当能量传递供体,而高掺杂浓度时Sm3+对Eu3+发光产生了猝灭作用。

关键词：红色荧光粉光致发光能量传递

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用于防伪标签的发光材料研究进展(特邀)

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光子学报 2022年第8期51卷 76-89页

作者：陈宝玖陈昕王礼王轶卓李磊徐赛大连海事大学理学院辽宁大连116026

货币、身份证件、有价证券及商品的伪造和仿制严重威胁国家政治安全、金融稳定,侵害社会团体及个人利益。防伪技术是防范和抑制造假和克隆行为的有效手段,基于发光材料的防伪标签是当前防伪领域的研究热点。本文主要介绍近年来用于防伪... 详细信息

货币、身份证件、有价证券及商品的伪造和仿制严重威胁国家政治安全、金融稳定,侵害社会团体及个人利益。防伪技术是防范和抑制造假和克隆行为的有效手段,基于发光材料的防伪标签是当前防伪领域的研究热点。本文主要介绍近年来用于防伪标签的发光材料的研究进展,包括用于防伪标签发光材料的种类、防伪材料的发光机理、实现防伪鉴别所使用的激励源、发光防伪标签的设计方法及制作技术和防伪标签的鉴别方法等。此外,本文还对当前发光防伪材料存在的问题,以及未来发展趋势作了系统分析。

关键词：发光材料防伪标签下移发光上转换长余辉光激励延迟荧光机械发光

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Concentration effect and temperature quenching of upconversion luminescence in Ba Gd_2ZnO_5:Er^(3+)/Yb^(3+) phosphor

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Journal of Rare Earths 2015年第7期33卷 686-692页

作者：周天民张艳秋吴中立陈宝玖 Department of Physics Dalian Maritime University

Er^3＋/yb^3＋ codoped zincate BaGd2ZnO5 phosphors were synthesized via a traditional solid state reaction. The crystal structure and phase purity were checked by means of X-ray dfluence of Eiffraction （XRD）, and the results showed that pure phase BaGd2ZnO5 phosphors with various Er^3＋/yb^3＋ concentrations were obtained. The Er^3＋ and Yb^3＋ doping concentrations on the green and red upconversion emissions was studied. It was found that both green and red upconversion emissions under 980 nm excitation were two-photon processes independent from the rare earth doping concentrations. However, the upconversion luminescence intensities greatly depended on the rare earth doping concentration. Furthermore, the population processes of upconversion luminescence and the quenching mechanisms were analyzed. The temperature-dependent green upconvcrsion luminescence was studied, and the temperature quenching process of two green upconversion emissions was modeled. The thermal quenching processes of the green upconversion emissions could be well explained by the model we proposed.

关键词： BaGd2ZnO5：Er^3＋/yb^3＋ phosphor solid state reaction upconversion crossover rare earths

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