共查询到19条相似文献,搜索用时 93 毫秒
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据媒体报导,一种环保耐用的稀土纳米材料节能灯不久前由哈尔滨市动力区创业中心研发成功。这种新型节能灯获得了国家发明专利和文用新型专利。据悉,该节能灯所用的节能材料是一种有机和无机纳米杂化发光材料,它由高聚物与稀土化合物纳米杂化发光材料合成,经反应后制成凝胶,再用热聚合方法制成新型的纳米节能材料。 相似文献
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北京大学化学与分子工程学院严纯华课题组日前在新型纳米稀土化合物的控制合成和性质研究中取得较大进展。他们首次以具有较低分解温度的稀土配合物为前躯体(如稀土苯乙酰丙酮和稀土三氟乙酸配合物等),在高沸点混合溶剂(油酸、油胺和十八烯)中通过调节前躯体的热分解方式和溶剂组成控制晶体的成核和生长过程,一步获得了高度晶化、尺寸均一可调、形貌可控、无团聚、易分散于非极性溶剂的、具有新颖结构的全系列单一或复合稀土氧化物和氟化物纳米材料。通过分散溶剂的调节和材料表面控制,上述纳米晶可白发组装成高度有序的超晶格结构。同时,相关化合物呈现出显著的纳米材料的结构和表面效应,产生了与相应的体相材料不同的光学性质。这一新型合成路线可推广用于复合稀土化合物、其它主族和过渡族化合物纳米材料的控制合成。 相似文献
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在制备掺杂型稀土高分子材料中,因大多数稀土化合物与树酯型高分子材料亲和力差而难以均匀分散于其中,所以材料往往透明性差、强度低,很难得到高稀土含量、高透明性的稀土材料,极大地限制了其应用。本文主要合成了以稀土铕为红色电致发光材料的三类材料,第一类是配合物单体,第二类是一系列主链上含有发光单元和空穴传输单元两种不同功能团的高聚物,第三类是一系列主链上含有发光单元的高聚物,再通过红外光谱、紫外光谱、荧光光谱等测试,讨论分析并对比其性能,以得出结论。 相似文献
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Research and development of nanoscale luminescent and laser materials are part of the rapidly advancing nanoscience and nanotechnology. Because of unique spectroscopic properties and luminescent dynamics of f-electron states, doping luminescent rare earth ions into nano-hosts has been demonstrated as an optimistic approach to developing highly efficient and stable nanophosphors for various applications. In this article, we review the most recent progress in spectroscopic measurements of rare earth ion-activated low-dimensional nanostructures including nanolayers, core-shells, nanowires, nanotubes, and nanodisks. Among a large volume of work reported in the literature on many members of the rare earth series including Ce3+, Pr3+, Nd3+, Eu3+, and Er3+, we focus on recent findings in the spectroscopic and luminescence properties of Eu3+ doped nanolayers, core-shells, and nanotubes, because Eu3+ ions have been extensively studied and widely used as an ideal probe for fundamental understanding of nano-phenomena. Specifically, the dependence of the optical properties of rare earth ions on nanostructures is discussed in detail. 相似文献
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目的 探究稀土高分子光学性能的研究情况,开发其应用潜力,从发光机理、制备、应用3个方面综述稀土高分子的研究进展,给后续的研究提供参考。方法 经过大量文献的搜集、翻阅,对发光稀土高分子的研究进展进行整理及总结。结果 稀土高分子的发光机理以中心稀土离子发光、天线效应和共荧光效应为主,按成键与否将其分为掺杂型稀土高分子和键合型稀土高分子,主要应用于农用塑料薄膜、防伪油墨、夜光纤维、荧光探针、太阳能电池等领域。结论 稀土高分子具有良好的综合性能,目前已应用于多个领域,深入研究稀土高分子的光学性能具有必要的科研意义和价值。 相似文献
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One-dimensional nanosized phosphors demonstrate special structural and photoluminescence properties, which have application potential in some optical fields. In this article, we present our recent progress on preparation and luminescence properties of some one-dimensional rare earth compounds and complexes, the core-shell oxide nanowires prepared by a two-step hydrothermal route, the nanowires of some inorganic compounds doped with rare earths and rare earth complexes/PVP composites prepared by the electrospinning method, and the rare earth complexes in the SBA-15 mesoporous molecule sieves. In these systems, some novel or improved photoluminescence properties are observed such as improved luminescence quantum yield, thermal stability and/or photostability, and depressed thermal effect in upconversion luminescence. 相似文献
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目的 从增强稀土离子发光的角度考察上转换发光调控及性能,综述稀土发光材料在光学防伪领域的应用,以期为上转换材料与包装材料的功能化研究提供参考。方法 检索近几年文献,介绍上转换发光纳米材料的发光机理、发光性能及调控、光学材料打印技术的研究进展。结果 稀土掺杂的上转换发光纳米材料表现出优异的发光性能,但随着粒径减小,纳米颗粒出现发光效率、量子产量低的问题。利用纳米颗粒表面钝化、表面等离子体耦合、与有机配体结合和外场调节等手段,可以使发光材料的发光效能显著增强。利用喷墨打印、丝网印刷、纳米压印光刻和气溶胶喷印等技术,可以使稀土掺杂的上转换发光纳米材料被打印成多样的防伪图案,在光学防伪、信息存储与标记等领域具有重大应用潜力,有望成为新型功能包装材料。结论 在光学材料合成技术、光学调控和打印技术的共同推动下,稀土掺杂上转换发光纳米材料因其特殊的光学特性,有望为功能化包装防伪技术作出贡献。 相似文献
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Vikram Awate Ratnesh Tiwari A. K. Shrivastava Neha Dubey Vikas Dubey 《Journal of Materials Science: Materials in Electronics》2018,29(6):4391-4401
This review includes research papers on different method of preparation of rare earth activated Sr2SiO4 phosphors and its luminescence studies. Here in Sr2SiO4 has attracted great interest due to its special structure features, excellent physical and chemical stability. Besides, it absorbs ultraviolet radiation and emits white light when activated by different rare earth ions. Different synthesis techniques were compared and it is found that sol–gel synthesis technique is best for preparation of rare earth activated Sr2SiO4 phosphors. Literature related to characterization techniques such as X-ray diffraction techniques, scanning electron microscopy, transmission electron microscopy and other studies are also compared. Photoluminescence studies for white light emitting diode of various rare earth phosphors are compared with Sr2SiO4 phosphor reported in this review. Also some luminescence techniques such as thermoluminescence glow curve analysis and some spectroscopic parameters are also compared. The review end with some important conclusion related to rare earth activated Sr2SiO4 phosphors with proper justifications. 相似文献
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In sulfur-based chalcogenide glass, i.e., a covalent amorphous solid, the addition of a small amount of Ga + CsBr switches the nearest neighbors of the Dy3+ dopant from S to Br, which results in significant enhancement in the lifetime of the excited 4f configurational states of Dy3+. The chemical preference between [GaS3Br]- and Dy3+ alters only the local structures of the involved rare earth ion. This atomic restructuring occurs spontaneously at a nanoscale during the melt-quenching process, without the need for further heat treatment, and thus improves the luminescence properties of the activator while keeping the thermal and mechanical properties of the parent host material unchanged. In this study, it is experimentally verified that externally applied DC electric fields can further tune the oscillator strengths of Dy3+ in Ge-S glass that contains Ga + CsBr. This experimental finding proves that mass transports driven by electric fields influence the optical properties of rare earth doped in the chalcogenide glass that is compositionally engineered in this study. 相似文献
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In recent years, the energy transfer between different rare earth ions and the luminescent properties of rare earth ions have been studied extensively. However, the research of luminescent properties, thermal stability and structural variations of organic compounds, as well as their energy transfer to rare earth ions in silica xerogel, have not been reported. Organic—inorganic composites have even more efficient luminescence than pure rare earth ions. We describe the fabrication of silica xerogels doped with phthalic acid and Tb3+, their luminescent properties and thermal stability. The results show that, in silica xerogels, phthalic acid can exist steadily at 300 °C, and it can transfer the energy that it has absorbed to Tb3+. 相似文献
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Bulk alkaline earth fluorides co-doped with optically active ions are prominent materials for luminescent applications. However, for phosphor materials the changeover to the nanoscale is a tightrope walk between achieving desirable features of small particles such as reduced light scattering and unwanted drawbacks such as a high surface defect concentration which is likely to result in quenching of luminescence. A new preparation route via ionic liquids allows obtaining pure and oxygen-free alkaline earth fluorides co-doped with Eu3+ and Gd3+ on the nanoscale with excellent quantum cutting abilities. 相似文献
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简要介绍了稀土发光材料的发光原理和八种制备方法,包括传统的高温固相反应法溶胶-凝胶法、水热合成法、低温燃烧合成法、化学沉淀法、微波辐射法、电弧法、CO2激光加热气相沉积合成法,总结了每种制备方法的优缺点,并对稀土发光材料的应用和发展前景进行了展望。 相似文献