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Optical spectroscopy and crystal-field strength of Cr^(3+) in various solid matrixes

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Rare Metals 2006年第1期25卷 51-57页

作者： XIA Haiping WANG Jinhao WANG Hongyin zhang Jianli zhang yuepin XU Tiefeng The Laboratory of Photo-electronic Materials Ningbo University Ningbo 315211 China

The Cr^3＋：BeAl2O4 crystal, Cr^3＋：LiNbO3 crystal, and ZnO-Al2O3-SiO2 glass-ceramic were obtained by the Czochralski technique, Bridgman method, and melting processing, respectively. The optical absorption and emission spectra of the above Cr^3＋-incorporated solid-state materials were recorded. The technical parameters for growing high-quality Cr^3＋：BeAl2O4 and Cr^3＋：LINbO3 crystals were obtained. The results indicate that the optical absorption and fluorescence spectra of Cr^3＋ show quite a few differences in various matrixes. The sharp line emissions were observed in the Cr^3＋：BeAl2O4 and Cr^3＋：LiNbO3 crystals. The crystal-field parameters （Dq） for Cr^3＋. in different matrixes were calculated from their corresponding spectra. It is indicated that Cr^3＋：BeAl2O4 and Cr^3＋：LiNbO3 belong to the high-field site crystal, while the Cr^3＋ ZnO-Al2O3-SiO2 glass and glass-ceramic belong to the weak-field site crystal.

关键词： special functional inorganic materials optical spectroscopy optical measurement Cr^3+ ion matrix

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 crys

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

Fullerenol-containing Materials Derived by Sol-gel Processing

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Journal of Materials Science & Technology 2004年第5期20卷 555-557页

作者： Haiping XIA, Zhaoyang JIANG, Jianli zhang, Jinhao WANG, yuepin zhang and Qiuhua NIELaboratory of Photo-electronic Materials, Ningbo University, Ningbo 315211, China Lab. of Photo-Electron. Mat. Ningbo Univ. Ningbo 315211 China

Water soluble fullerenols were synthesized and incorporated in SiO2, SiO2-TiO2, GPTMS-SiO2, GPTMS-ATPS inorganic and organic-inorganic materials by sol-gel processes. The maximum concentrations of C60(OH)n and C70(OH)n in the obtained SiO2 gels were estimated to be about 0.6% and 1.5% in weight, respectively. The characteristics of the UV/visible spectra of fullerenols in H2O and various gels were measured and compared. The thermal stability of fullerenols in gels was investigated with differential thermal analysis (DTA). The results indicate that the absorption features of fullerenols in solid gels are similar to those in H2O and the fullerenols in SiO2 are stable at 400℃. The optical limiting effect of the fullerenols was investigated preliminarily.

关键词： Water soluble fullerenol Sol-gel chemistry Thermal stability Optical properties

Silicon-phthalocyanine bonding with SiO_2 matrix and its strong optical limiting effects

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Chinese Science Bulletin 2000年第23期45卷 2198-2203页

作者： XIA Haiping, PU Bingyin, zhang yuepin, zhang Jianli, FANG Jianghua & WANG CunkuanDepartment of Chemistry, Ningbo University, Ningbo 315211, China Correspondence should be addressed to Xia Haiping Department of Chemistry Ningbo University Ningbo China

Silicon-phthalocyanine (SiPc) is chemically bonded to 3-aminopropltriethoxysilane (NH2(CH2)3Si(OC2H5)3, KH550) by the nucleophilic substituted reaction between the active chlorine of silicon dichlorine phthalocyanine (SiPcCI2) and amino-group of KH550. The reacted product is hybridized with 3-glycidoxypropltrimethoxysilane (CH2OCHCH2O(CH2)3Si(OCH3)3, KH560) with sol-gel processing to form sol-gel inorganic material with good physical-chemical and optical properties. Due to tethering SiPc to the network, the aggregation of SiPc is effectively prevented in sol-gel derived matrix, and the doping concentration of SiPc in the form of monomer in the matrix is greatly enhanced. The cross-linkage of SiPcCI2 and KH550 is estimated and confirmed with FT-IR spectra. The optical limiting effects (OLE) of the gel with different content of SiPc are investigated with a frequency double Q-switched Nd3+:YAG laser of 8 nsec. pulse.

关键词： silicon dichlorine phthalocyanine amino-group cross-linkage inorganic non-crystal matrix optical limiting effect.

Luminescent properties of Ce^(3+)-doped transparent oxyfluoride glass ceramics containing BaGdF＿5 nanocrystals

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Journal of Rare Earths 2015年第1期33卷 13-19页

作者：王倩欧阳绍业张为欢杨斌张约品夏海平 Key Laboratory of Photo-Electronic Material Ningbo University

The transparent oxyfluoride glass ceramics containing Ba Gd F5 nanocrystals were prepared with a composition of 42 Si O2-12Na2O-16Al2O3-24 Ba F2-4Gd2O3-2Ce F3（mol.%） by thermal treatment technology. The typical DSC curve, X-ray diffraction（XRD） and transmission electron microscopy（TEM） patterns were measured. The transmission spectra and luminescent properties were investigated. The decay times of the Gd^3＋ ions at 312 nm excited with 275 nm for the Ce^3＋ ions doped glass and glass ceramics specimens and the energy transfer process between Gd^3＋ ions and Ce^3＋ ions were also studied. The XRD analysis and the TEM images confirmed the generation of the spherical Ba Gd F5 nanocrystals. Compared with the PG specimen, the intensity of the luminescence spectra of the glass ceramics specimens was apparently enhanced with the heat treatment temperature increasing, and a blue shift in the excitation spectra and the emission spectra of glass ceramics specimens was obviously observed. In the fluorescence decay curves of the Gd^3＋ ions, it could be obviously observed that the fluorescent intensity decays in the Ce^3＋ ions doped glass and glass ceramics specimens decreased rapidly with the increase of the heat treatment temperature. In addition, the energy transfer efficiency from Gd3＋ions to Ce^3＋ ions was also calculated.

关键词： transparent oxyfluoride glass ceramics BaGdF5 nanocrystals luminescent properties energy transfer rare earths

Luminescent properties of Ce^(3+)/Tb^(3+) co-doped glass ceramics containing YPO_4 nanocrystals for W-LEDs

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Journal of Rare Earths 2016年第5期34卷 464-469页

作者：张志雄张约品冯治刚王成夏海平张新民 Key Laboratory of Photo-electronic Materials Ningbo University

Ce^3＋/Tb^3＋ co-doped transparent glass ceramics containing YPO4 nanocrystals were prepared using high temperature melting method,and their structural and luminous properties were *** analysis and TEM images confirmed the existence of YPO4 nanocrystals in glass *** transmission spectra proved that the glass ceramics specimens still maintained a high *** the excitation and emission spectra of the Ce^3＋ and Tb^3＋ single-doped and co-doped glass and glass ceramics were discussed,which proved that the glass ceramics had better luminescent *** the near ultraviolet（331 nm）excitation,the broadband emission located at 385 nm was observed which was ascribed to 5d→~2F（5/2） and ~2F（7/2） transition of Ce^3＋ *** characteristic sharp peaks centered at 489,543,578 and 620 nm originated from the ~5D4 to ~7FJ（J=6,5,4,3）of Tb^3＋ *** decay time of Tb^3＋ ions at 543 nm and the relevant energy levels of Ce^3＋ ions and Tb^3＋ ions illustrated the transfer process from Ce^3＋ ions to Tb^3＋ *** best CIE chromaticity coordinate of the glass ceramics specimen was calculated as（x=0.3201,y=0.3749）,which was close to the NTSC standard values for white（x=0.333,y=0.333）.All the results suggested that the YPO^4-based Ce^3＋/Tb^3＋ co-doped glass ceramics could act as potential luminescent materials for white light-emitting diodes.

关键词： glass ceramics YPO4 nanocrystals Ce^3+/Tb^3+ co-doped luminous properties white light-emitting rare earths

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TiO2包覆单分散SiO2球的制备

稀有金属材料与工程 2004年第z1期33卷 193-195页

作者：徐键夏海平张约品宁波大学浙江宁波315211 宁波大学浙江宁波315211 宁波大学浙江宁波315211

分别采用钛酸异丙酯和钛酸丁酯为先驱体,对所制备的单分散氧化硅球(Ф≈400 nm)进行了1次和2次包覆TiO2层,获得了单分散的SiO2-TiO2芯-壳结构的球;采用TEM,SEM和EDS对所得SiO2-TiO2的球的大小、形貌和球中硅、钛含量进行了表征.研究结... 详细信息

分别采用钛酸异丙酯和钛酸丁酯为先驱体,对所制备的单分散氧化硅球(Ф≈400 nm)进行了1次和2次包覆TiO2层,获得了单分散的SiO2-TiO2芯-壳结构的球;采用TEM,SEM和EDS对所得SiO2-TiO2的球的大小、形貌和球中硅、钛含量进行了表征.研究结果表明:采用钛酸异丙酯作为先驱体可获得氧化钛层较薄但无粘结的SiO2-TiO2芯-壳结构的球(φ可达500 nm);而采用钛酸丁酯作为先驱体时,则可获得较厚但粘结的SiO2-TiO2芯-壳结构的球(φ可达600nm).

关键词： SiO2-TiO2球芯-壳结构胶体颗粒

用溶胶-凝胶法制备铜酞菁固体材料及其光学性质

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硅酸盐学报 2001年第2期29卷 114-118页

作者：夏海平章践立张约品聂秋华宁波大学信息科学与工程学院

运用溶胶-凝胶技术 ,利用γ-氨基丙基三乙氧基硅烷 (3-aminopropyltriethoxysilane ,NH2 (CH2 ) 3Si(OC2 H5 ) 3,KH5 5 0 )中氨基与 4-羧基铜酞菁 [(Tetracarboxyphalocyaninato)copper(Ⅱ ) ,CuPc(COOH) 4]中羧基的化学作用 ,成功地把CuPc(COOH ) 4以较大浓度均匀地掺入到KH5 5 0与γ-缩水甘油醚基丙基三甲氧基硅烷 (3-glycidoxypropl-trimethoxysilane,CH2 OCHCH2 O(CH2 ) 3Si(OCH3) 3,KH5 6 0 )为先驱体的凝胶介质中 .红外光谱表征了CuPc(COOH) 4与KH5 5 0的化学反应过程 .用波长为 5 32nm ,脉宽 8ns的Nd3 + ∶YAG激光对复合材料的光限幅特征作了初步的研究 .

关键词：铜酞菁溶胶-凝胶法结构连接光学性质

ZnO对Eu:LiNbO_3晶体的性能及光谱性质影响

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光学学报 2005年第8期25卷 1087-1090页

作者：夏海平王金浩章践立张约品宁波大学光电子功能材料研究所宁波315211

应用坩埚下降法技术,以同成份化学摩尔分数[x(Li2O)=48.6%,x(Nb2O5)=51.4%]为原料,生长出了以不同Zn,Eu双掺杂的LiNbO3晶体。测定了晶体下部与上部的X射线衍射图(XRD)、激发光谱、荧光光谱以及声子边带谱。Zn的掺杂量对Eu3+离子在晶体... 详细信息

应用坩埚下降法技术,以同成份化学摩尔分数[x(Li2O)=48.6%,x(Nb2O5)=51.4%]为原料,生长出了以不同Zn,Eu双掺杂的LiNbO3晶体。测定了晶体下部与上部的X射线衍射图(XRD)、激发光谱、荧光光谱以及声子边带谱。Zn的掺杂量对Eu3+离子在晶体中的分布产生很大的影响。Zn掺杂摩尔分数为3%时,Eu3+离子在进入晶格时受到有效的压制。随着Zn掺杂摩尔分数提高,达到6%时,压制作用减弱。从Zn2+离子在LiNbO3中随浓度变化的分凝情况以及对Eu3+离子的排斥作用解释了Eu3+离子分布的原因。同时测定了Zn掺杂样品的声子边带谱。

关键词：光学材料锌铕双掺铌酸锂品体坩埚下降法 Eu^3+离子浓度分布光谱