稀土发光玻璃的制备与性能研究

利用高温固相合成法在还原气氛中,合成了新型长余辉发光粉CaxSr1-xAl2O4:Eu 2 ,并以硼酸盐体系玻璃B2O3-(Na,K)2O-XO和硅硼酸盐体系玻璃SiO2-B2O3-(Na,K)2O-X2O-XO 的低熔点玻璃作为载体,掺杂该发光粉合成了稀土蓄光发光玻璃.实验改进了合成发光玻璃的热处理方法,提出二阶段的热处理方案,确定了发光玻璃的最佳合成温度分别为820℃和880℃.并根据SEM结果,对两种发光玻璃的表面质量及发光强度进行了对比分析,发现合成的硼硅酸盐发光玻璃的稳定性和发光效果要好于硼酸盐发光玻璃.     

长余辉蓄光玻璃的制备及其性能研究

利用传统陶瓷制备方法合成了SrAl2O4:Eu,Dy长余辉发光粉体,该磷光体主发射波长位于520nm,余辉时间长达8h以上。并以硼硅酸盐低熔点玻璃为底材,掺杂该发光粉体,在一定温度下烧成,结果制得长余辉蓄光玻璃。研究还表明,烧成温度对该玻璃的发光性能影响较大,随着温度的升高,发光强度及余辉时间明显下降。     

草酸盐共沉淀法制备CaTiO3:Pr3+长余辉发光材料的性能研究

采用草酸盐共沉淀法在700～1000℃下制备出了CaTiO3:Pr3+红色长余辉发光材料;用同步热分析仪、X射线衍射仪、透射电镜和荧光分光光度计对产物进行了测试分析;就煅烧温度对产物的发光特性的影响进行了讨论;结果表明,煅烧温度为900℃时草酸盐共沉淀法制备的CaTiO3:Pr3+红色长余辉发光材料的发光性能最好.     

槽沉法制备长余辉发光玻璃微球

选择铝硼硅酸盐玻璃体系，高温熔融法制备了Eu，Dy掺杂的铝硼酸盐基质透明玻璃，并采用槽沉法制备了透明玻璃微球．利用XRD、SEM和荧光光谱对样品进行分析．结果表明：该玻璃微球粒径分布范围窄，光学性能好，其折射率为1．690；单掺杂和双掺杂玻璃微球均具有长余辉发光性能，单掺杂Eu^2＋发光峰位于460nm，而双掺杂Eu^2＋、Dy^3＋的发光峰分别位于456和452nm，并且样品的发光时间达到15h以上。     

长余辉发光材料的研究进展

长余辉发光材料因其具有特殊的储能发光性能,是一类绿色环保型材料.综述了主要体系长余辉发光材料的研究历程,总结了长余辉材料的制备方法和余辉效应,概括了长余辉发光研究上存在的问题,提出了今后研究和应用的发展方向.     

草酸盐共沉淀法制备CaTiO_3∶Pr~(3+)长余辉发光材料的性能研究

采用草酸盐共沉淀法在700~1000℃下制备出了CaTiO3∶Pr3+红色长余辉发光材料;用同步热分析仪、X射线衍射仪、透射电镜和荧光分光光度计对产物进行了测试分析;就煅烧温度对产物的发光特性的影响进行了讨论;结果表明,煅烧温度为900℃时草酸盐共沉淀法制备的CaTiO3∶Pr3+红色长余辉发光材料的发光性能最好。     

聚酯丙烯酸发光涂料的研制

为了提高发光涂料的耐候性、耐酸碱性、耐油性、耐腐蚀性和力学性能以及余辉强度和余辉时间,对聚酯丙烯酸树脂和铝酸锶铕发光材料的制备方法进行了研究,并将发光材料分散于聚酯丙烯酸树脂中,制备出了高性能的发光涂料.结果表明:用无色透明且透光性良好、特别是紫外线透过率高、透湿性小且耐水性、耐酸碱性、耐候性和力学性能优良的聚酯丙烯酸树脂作为主要成膜物质,将铝酸锶铕发光材料分散于聚酯丙烯酸树脂中制成的发光涂料涂抹性能好,耐腐蚀性、耐油性、耐酸碱性和耐候性强,力学性能优良,余辉亮度强,用照度200 lx的D65光源照射4 min的余辉亮度在10min时为20 mcd/m2,在60 min时为6 mcd/m2;制得的发光涂料余辉时间长,余辉时间在1 000 min以上,为优质的发光涂料.     

长余辉发光材料的研究进展

铝酸盐长余辉发光材料因为其优异的性能,是一类新型储能和环保材料.本文主要综述了90年代发展起来的铝酸盐体系长余辉发光材料的研究进展.总结了铝酸盐长余辉材料的发光特征和长余辉特性,指出了制备技术上的最新方法,概括了长余辉发光模型,并提出了今后研究和应用的发展方向.     

掺杂稀土CaAl 2O4基发光材料的制备及其发光机制

用固相烧结法制备了亮度高、余辉时间长的CaAl2O4:Eu,RE(RE为Nd,Dy)发光粉体材料,并对其发光性能进行了研究。发光粉体的发射光谱表明,其主发射峰均位于440nm左右。余辉衰减曲线证明其余辉衰减过程存在快速衰减和慢衰减两个过程。对于长余辉发光机制,认为Nd,Dy的加入起到了陷阱能级作用,从而延长了发光时间,增强发光亮度。并且在此基质材料中,Nd的陷阱深度比Dy的更合适,因而CaAl2O4:Eu,Nd的发光性能要优于CaAl2O4:Eu,Dy。     

环氧改性醇酸树脂发光涂料的研制

以环氧改性醇酸树脂为成膜物质,添加稀土发光材料(SrAl2O4∶Dy3 ,Eu2 )制备出高性能发光涂料,并介绍配方及工艺。结果表明,所得涂料的干燥性好,耐盐水性,耐盐雾性,和耐化学品性佳,发光性能优良,余辉亮度强且余辉时间长,为优质的发光涂料。     

Novel highly luminescent europium dinitrosalicylates

A series of lanthanide dinitrosalicylates M₃Ln(3,5-NO₂-Sal)₃ · nH₂O (Ln = Eu, Gd; M = Li, Na, K, Cs) was synthesized. It was found that the luminescence efficiency of some M₃Eu(3,5-NO₂-Sal)₃ · nH₂O compounds was near to the high efficiency of europium dibenzoylmethanate with 1,10-phenanthroline, Eu(DBM)₃ · Phen. The luminescence excitation spectra, electron-vibrational luminescence spectra, and vibrational IR spectra were investigated. The energy of the lowest excited triplet state of the ligand was obtained from phosphorescence spectra of M₃Gd(3,5-NO₂-Sal)₃ · nH₂O, M(3,5-NO₂-HSal) · nH₂O, and M₂(3,5-NO₂-Sal) · nH₂O. The details of the structure of compounds were discussed. The influence of different M-cations on the Eu³⁺ luminescence efficiency and on the processes of excitation energy transfer to a Eu³⁺ ion was analyzed. The presence of large alkali metal cations in lanthanide dinitrosalicylates and an increase in the temperature weaken the network of hydrogen bonds and, to some extent, the “ligand–metal” bonds. This is a cause of a long-wavelength shift of the intraligand charge transfer (ILCT) band in Eu³⁺ excitation spectra arising at inclusion of Cs⁺ instead of Li⁺ cations in the crystal lattice and at the heating of compounds. A change of the energies of ligand electronic states at substitution of Li⁺ and Na⁺ for Cs⁺ can give a tenfold enhancement of the Eu³⁺ luminescence efficiency at 300 K.     

Novel highly luminescent europium dinitrosalicylates

A series of lanthanide dinitrosalicylates M₃Ln(3,5-NO₂-Sal)₃ · nH₂O (Ln = Eu, Gd; M = Li, Na, K, Cs) was synthesized. It was found that the luminescence efficiency of some M₃Eu(3,5-NO₂-Sal)₃ · nH₂O compounds was near to the high efficiency of europium dibenzoylmethanate with 1,10-phenanthroline, Eu(DBM)₃ · Phen. The luminescence excitation spectra, electron-vibrational luminescence spectra, and vibrational IR spectra were investigated. The energy of the lowest excited triplet state of the ligand was obtained from phosphorescence spectra of M₃Gd(3,5-NO₂-Sal)₃ · nH₂O, M(3,5-NO₂-HSal) · nH₂O, and M₂(3,5-NO₂-Sal) · nH₂O. The details of the structure of compounds were discussed. The influence of different M-cations on the Eu³⁺ luminescence efficiency and on the processes of excitation energy transfer to a Eu³⁺ ion was analyzed. The presence of large alkali metal cations in lanthanide dinitrosalicylates and an increase in the temperature weaken the network of hydrogen bonds and, to some extent, the “ligand–metal” bonds. This is a cause of a long-wavelength shift of the intraligand charge transfer (ILCT) band in Eu³⁺ excitation spectra arising at inclusion of Cs⁺ instead of Li⁺ cations in the crystal lattice and at the heating of compounds. A change of the energies of ligand electronic states at substitution of Li⁺ and Na⁺ for Cs⁺ can give a tenfold enhancement of the Eu³⁺ luminescence efficiency at 300 K.     

纳米纤维素发光材料研究进展

纳米纤维素发光材料不仅具有发光基团特有的光物理或光化学性能,还具备纳米纤维素的可生物降解、生物相容、环境友好等特性,拓展了功能化纤维材料的应用领域.根据制备方法,纳米纤维素发光材料可分为三类:纳米纤维素/碳量子点复合发光材料、纤维素发光碳量子点和纳米纤维素/荧光染料复合发光材料.纳米纤维素发光材料具有独特的光学特性及结...     

Can we make silica luminescent?

It is still a challenge to develop optoelectronic or even photonic devices based on silicon technology. Silicon and its oxide, as well-known, do not possess direct electronic band transitions and, therefore, are not luminescent. The remaining weak light emission is based on intrinsic and extrinsic defect luminescence. Thus our investigations are extended to ion implantation, mainly to over-stoichiometric injection or isoelectronic substitution of the both constituents silicon or oxygen, i.e. by ions of the group IV (C, Si, Ge, Sn, Pb) or the group VI (O, S, Se). Such implantation produces new luminescence bands in silica layers, partially with optical electronic–vibronic transitions and respective multimodal spectra. In this context, special interest should be directed to low-dimension nanocluster formation in silica layers.     

Holographic patterning of luminescent photopolymer nanocomposites

Volume phase gratings in the photopolymerisable composites, containing luminescent nanoparticles have been fabricated for the first time. Nanoparticles of LaPO₄, doped by Ce³⁺ and Tb³⁺ ions (the trade name is REN-X-green) with high luminescence quantum yield were used as a luminescent inorganic additive. The holographic gratings in such materials are formed as a result of the diffusion distribution of the nanoparticles during exposure of photopolymerisable composites to interference pattern. The influence of the pre-polymer formulation and the holographic patterning parameters on the grating formation is comprehensively investigated. The use of the optimised pre-polymer syrup containing two monomers with sufficiently different polymerisation rates allows fabrication of gratings with diffraction efficiency up to 80% at low optical losses (< 5%) (20 μm film thickness). To obtain maximum diffraction efficiency the intensity and the period of the interference pattern were optimised for each formulation. In addition maximum diffraction efficiency was achieved with the nanocomposites containing 30–32 wt.% of nanoparticles. On the other hand the highest possible modulation of the nanoparticles' concentration was obtained for the concentration of about 20 wt.%. In this case maximum ordering of the nanoparticles in the polymer matrix is achieved. The photoluminescence of the nanoparticles within the homogeneous polymer film and within the grating has been measured. The example application of the photopolymerisable composite containing luminescence inorganic nanoparticles in holographic security technology has been demonstrated.     

Can we make silica luminescent?

It is still a challenge to develop optoelectronic or even photonic devices based on silicon technology. Silicon and its oxide, as well-known, do not possess direct electronic band transitions and, therefore, are not luminescent. The remaining weak light emission is based on intrinsic and extrinsic defect luminescence. Thus our investigations are extended to ion implantation, mainly to over-stoichiometric injection or isoelectronic substitution of the both constituents silicon or oxygen, i.e. by ions of the group IV (C, Si, Ge, Sn, Pb) or the group VI (O, S, Se). Such implantation produces new luminescence bands in silica layers, partially with optical electronic–vibronic transitions and respective multimodal spectra. In this context, special interest should be directed to low-dimension nanocluster formation in silica layers.