1.5μm波段超细氟化物上转换发光材料的合成及发光机理研究

The situation that InGaAs is so difficult to be prepared restricts seriously the communications development. A economically feasible "phosphor coating" short infrared CCD technology was paid full attention all over the world. To find one kind of ultra fine phosphor with high luminescence intensity is the precondition of this technology, while the current phosphor possesses so much defects, such as the coarse particle size, the low resolution, the requirment of charging energy. This project will study one kind of fluoride ultrafine upconversion phosphor, and will put emphasis on the low-temperature combustion synthesis of the sample in order to match the screen of CCD, to obtain the phosphor sample sensitive to 1.5μm, with emission of 500-700nm, particle size of 1μm. The research contents include the upconversion mechanism, the effect of substrate, dopant content and combustion art on the particle size and the luminescence properties, and the relationship between the infrared ecxitation condition and the particle properties.

InGaAs材料制备困难、国内研究不成熟，制约通信用1.5μm波段探测器件的发展。经济可行的"荧光粉涂层"短波红外CCD技术近年受到国际高度重视，颗粒均匀细小、发光亮度高的上转换发光粉是实现该技术的先决条件，而目前该技术可应用的发光粉存在颗粒度粗影响分辨率、需充能等不足。 本项目研制超细氟化物上转换发光材料，为满足CCD涂屏工艺对荧光粉提出的颗粒细且亮度高的特殊要求，着力研究通过低温燃烧工艺合成超细氟化物，辅以特殊热处理修复晶格缺陷，获得发光峰位于500-700nm、中心粒径约1μm、室温条件针对1.5μm波段高效响应的上转换发光超细粉。阐明上转换发光机制；揭示基质组成、掺杂浓度、燃烧工艺对粉体颗粒度及发光性能影响的规律和机制；阐明红外激发条件、红外响应阈值、颗粒度、发光亮度之间的关系和规律。

经济可行的“荧光粉涂层”短波红外CCD技术近年受到国际高度重视，颗粒均匀细小、发光亮度高的上转换发光粉是实现该技术的先决条件，而目前该技术可应用的发光粉存在颗粒度粗影响分辨率、需充能等不足。. 针对CCD涂屏工艺对荧光粉提出的颗粒细且亮度高的应用需求，项目采用低温燃烧法合成出对1550nm红外光具有红外-可见转换发光效应的超细氟化物上转换发光材料。通过正交实验设计，研究确定出四元阳离子的最佳组成配比。系统研究确定了燃料种类及用量、分散剂种类及用量对样品发光性能的影响规律。燃烧法制备出的材料样品由于反应非常迅速，因而材料往往存在很多表面缺陷，本项目对低温燃烧合成的纳米级粉体样品进行热处理工艺研究，修复样品表面缺陷的同时还要注意粒度的适度增长，研究确定实现既细且亮较为理想粉体效果的最佳工艺参数。