【作者】 夏艳琴；

【导师】 刘政威；

【作者基本信息】 湘潭大学 ， 物理电子学， 2006， 硕士

【摘要】 上转换发光在全固态激光器,显示设备和光放大器等方面具有重要的应用价值,一直以来受到了广泛关注。本文分别采用高温固相法和沉淀法合成了以氧化物和氟化物为基质的稀土离子掺杂上转换发光材料,结合980nm激发下的光谱图对其上转换发光特点及发光机理进行了分析,并初步探讨了掺杂方式和制备条件对上转换发光效率的影响。本文共五章,系统地阐述了上转换的研究背景、研究理论,以及本人在攻读硕士学位期间所做的部分工作。本文前两章主要介绍了上转换研究领域的一些基础知识。简要地总结了上转换的发展历程和研究现状,展示了目前被广泛研究的上转换发光材料体系,并对上转换材料的制备方法及工艺、应用前景、研究手段和研究重点进行了简要说明,指出了上转换研究中存在的、急于解决的一些问题及其解决途径,介绍了上转换研究的理论基础,给出了上转换的各种发光机制。第三章中通过高温固相法合成了以Bi2O3为基质材料的Er3+,Yb3+离子共掺杂上转换发光材料,制备出了红绿光强度比远远高于氟化物的红光样品,测试了样品在980nm激光激发下的上转换发光,并且对其发光现象进行了解释。第四章中分别采用沉淀法和高温固相法制备了NaYF4:Yb3+,Tm3+双掺杂蓝光样品,讨论了沉淀法所制备样品中Yb3+离子掺杂浓度对蓝色上转换发光的影响,得到了Yb3+离子的最佳掺杂浓度。对两种条件下所制备的成分相同的样品的发光强度进行了比较,发现沉淀法制备的样品发光性能更加优良。第五章在前一章的基础上采用沉淀法合成了Er3+,Yb3+,Tm3+三掺杂NaYF4基质上转换发光材料,Tm3+离子的浓度范围在0到0.6之间变化,发现上转换发光强度随着Tm3+离子浓度的增加而降低。分析了其发光特性和发光机制,研究了不同退火温度与样品发光性能和材料结构之间的关系,得到了最佳退火温度。最后总结了所做的工作,并且进行了展望。更多还原

【Abstract】 Owing to the important applications in solid-state lasers, display devices, optical amplifiers and so on, up-conversion luminescence have attracted a great deal of attentions. In this dissertation, two kinds of rare earth doped materials based on oxide and fluoride respectively were fabricated by different synthetic methods. According to the emission spectra of the materials at 980nm excitation, the characteristics and the up-conversion mechanisms of the luminescence were studied. In the meanwhile the dependence of the emission performance of the samples on the synthetic method as well as the doping of rare earth ions were discussed. This paper consists of five chapters, firstly expounding the background and the foundational theories, and then introducing the author’work during the course of acquiring the Master’s degree.In the first and second chapters of the dissertation, the history of the development and the Hotpoint of this filed were summarized briefly. The widely studied material systems that the up-conversion samples based on were presented. The preparation technology, potential applications and research methods were reviewed. The urgent problems which have not been solved in the studies of up-conversion as well as the possible way to solve them were shown. The basic theories and the up-conversion mechanisms were discussed.In chapter 3, Er3+/Yb3+ co-doped samples of red predominating emissions based on Bi2O3 that were prepared though high temperature solid-state reaction displays that the intensity ratio of red emission to green emission is higher than that of fluoride, and the properties of up-converted emissions under 980nm excitation of the samples were also dealt with.In chapter 4, a group of NaYF4:Yb3+,Tm3+ samples were prepared by high temperature solid-state reaction and Precipitation method, respectively. The effects of Yb3+ concentration on emission intensities were investigated, and the optimized Yb3+ concentration was obtained. From the comparison of the emission intensities of the samples with the same compositions fabricated by different synthetic methods, a conclusion can be drawn that the sample synthesized by Precipitation method is much better than that synthesized by high temperature solid-state reaction.Based on the investigation of chapter 4, the NaYF4:Er3+,Yb3+,Tm3+ samples were prepared by Precipitation method. When the concentration of Tm3+ changes from 0 to 0.6mol%, we found that the intensity of up-conversion luminescence decreases更多还原