【作者】 贾智帅；

【导师】 由芳田；

【作者基本信息】 北京交通大学 ， 材料物理与化学， 2010， 硕士

【摘要】 稀土发光材料的应用一直是重点的高新技术领域,在照明、显示、信息传递等领域都有广泛的应用。上转换发光材料能够将红外光子转变成可见光,在医学探测上有广阔的应用前景,而量子剪裁发光材料能够将高能量的光子转变成两个或两个以上低能量的光子,提高能量利用效率铝酸盐基质材料的化学性质稳定、抗热和抗机械力性能优秀,在紫外和真空紫外波段有很强的吸收,是一类广受重视的基质材料,并且在PDP显示领域和无汞荧光灯方面有广泛的应用。YAG是一种钙钛矿结构的铝酸盐,是一种好的激光和闪烁体基质,而与其结构相类似的LaAlO3被作为发光材料研究的报道却很少。本论文主要做了以下工作：1.采用共沉淀法制备了纳米LaAlO3基质,研究了不同反应条件对产物结晶性能与粒径的影响,X射线衍射图谱和SEM表明,升高温度和提高反应时间都可以使LaAlO3的结晶性能变好,但是升高温度会使其粒径变大,导致团聚。2.研究了LaAlO3基质中Tb3+的发光性能,常温下光谱性质表明,当Tb3+的掺杂浓度小于1%时,5D3、5D4发光强度随浓度的增大而增强,当浓度达到1%时会发生浓度猝灭,5D3的发光强度会减小。升高温度和延长反应时间都可以使Tb3+的发光变强。3.研究了LaAlO3基质中Tb3+、Yb3+离子之间的能量传递过程,结果表明以980nm激发样品时,会发生上转换发光,为双光子过程。在Tb3+、Gd3+共掺杂的基质中,观察到了Gd3+对Tb3+的能量传递,对Tb3+起到敏化作用。4.制备并表征了YAG:Pr3+,Eu3+体系,对Pr3+,Eu3+之间的能量传递有了初步的认识。更多还原

【Abstract】 The application of Rare Earth Luminescent Materials has been the focus in high-tech fields, such as lighting, display, messaging and so on. Upconversion luminescence materials can change infrared photons into visible light, while quantum cutting light materials can absorb high-energy photons and release double or more low-energy photons, so the former has a great prospect in bio-detection and the later may raise energy efficiency.Aluminates substrate phosphors had attracted a lot of attention because of their excellent chemical, thermal stability and highly absorption of ultraviolet and vacuum ultraviolet photons. YAG, whose molecular formula is YAl5O12 has been a good laser and seintillator matrix, while LaAlO>3 has not received enough attention although its structure is similar to YAG.The research include the following contents:1. LaAlO3 matrix was prepared by co-precipitation method. The effect on the performance and size of crystals was studied in different reaction conditions. X-ray diffraction and SEM showed that higher temperature and longer reaction time would improve the crystallization properties of LaAlO3, but the higher temperature would increase the particle size, inducing reunion.2. The luminescence properties of Tb3+doped in LaAlO3matrix has been studied. Spectral on room temperature showed that the luminescence intensity increased with increasing concentration when the Tb3+doping concentration was less than 1% and opposite when the concentration was more than 1%. Higher temperature and longer reaction time would enhance Tb3+luminescence intensity.3. We studied the energy transfer between Tb3+ and Yb3+ ion in LaAlO3 matrix. When the samples was excited by light in 980nm the up-conversion process would occur, indicating the two-photon process. When the light was changed to 193nm, down-conversion would occur. The energy transfer from Gd3+ toTb3+ in matrix was observed, sensitizing Tb3+ions.4. Preparation and Characterization of a YAG/Pr3+, Eu3+ system helped the understanding of the energy transfer between Pr3+ and Eu3+.更多还原