《稀土氧化物透明激光陶瓷粉体的制备与表征》由会员分享，可在线阅读，更多相关《稀土氧化物透明激光陶瓷粉体的制备与表征（82页珍藏版）》请在金锄头文库上搜索。
1、烟台大学 硕士学位论文 稀土氧化物透明激光陶瓷粉体的制备与表征 姓名：张溶 申请学位级别：硕士 专业：材料学 指导教师：秦连杰 20090401 烟 台 大 学 硕 士 学 位 论 文 烟 台 大 学 硕 士 学 位 论 文 I 摘 要 稀土氧化物透明陶瓷以其良好的物理性能、优异的光学性能，越来越受到研究人员的 关注。与单晶和玻璃作为激光材料相比它具有很多优点，例如可大尺寸制备，成本低，掺 杂浓度高等，因此它被预言是单晶激光材料和玻璃激光材料的替代品。 本文分别用络合共沉淀法和溶胶凝胶燃烧法制备了掺钕氧化钆镧粉体和掺铒氧化钆 粉体透明激光陶瓷粉体，通过对这两种方法的对比，得出共沉淀法比溶胶凝胶
2、燃烧法更适 合制备这种稀土氧化物粉体。然后又用沉淀法制备了 Nd:Y2O3和 Nd:YAG 两种透明激光 陶瓷粉体，通过使用的三种不同的沉淀剂进行对比，得出在共沉淀法中复合沉淀剂最适合 制备稀土氧化物透明陶瓷粉体。分别选用综合热分析仪（TG-DTA） ，X 射线粉末衍射仪 （XRD） 、扫描电子显微镜（SEM）和傅立叶变换红外光谱仪（FTIR）对所制备粉体的热 分解过程、物相组成、形貌和纯度进行分析。 用络合共沉淀法制备的粉体经不同温度热处理后均为立方相结构，呈薄片状，均一， 颗粒小，晶界清晰。用溶胶凝胶燃烧法制备的粉体随着热处理温度的升高由单斜相转变为 立方相， 经1100C热处理后的粉体为
3、单斜相， 蓬松、 多孔， 有一定程度的团聚， 经1300C 热处理后转变为立方相，颗粒呈球状，均一，颗粒大，晶界清晰。用溶胶凝胶燃烧法，采 用柠檬酸和EDTA组成的混合燃烧剂制备的Er:Gd2O3粉体也是蓬松，多孔，形貌不规则， 且有一定程度的团聚， 但是混合燃烧剂的使用使制备的Gd2O3粉体均为立方相而不再含有 单斜相， 从而有利于其粉体发光性能的提高。 用草酸共沉淀法制备的Er:Gd2O3粉体除形成 草酸盐外，在热处理过程中还形成了碳酸氧化物，草酸盐和碳酸氧化物的热分解温度分别 大约是401C 和642C，用草酸共沉淀法制备的Er:Gd2O3粉体颗粒形貌规则，成片状，颗 粒均一，晶界清晰。
4、粉体经900C热处理后粉体片状颗粒平均宽度大约1m，平均厚度大 约 20nm。两种方法制备的粉体均易吸收空气中的 CO2 和 H2O 在颗粒表面形成 CO32-和 OH-。综合对比两种方法发现，共沉淀法更适合制备此种稀土氧化物透明激光陶瓷粉体。 沉淀法中以尿素为沉淀剂制备粉体时，需要反应条件较高，且易生成硫酸盐难以除 去；以草酸为沉淀剂制备的粉体颗粒较大，不均一，形状不规则，且 Al3+和 Y3+不易被草 酸根同时沉淀；综合对比发现，由碳酸氢铵和氨水组成的复合沉淀剂制备 Nd:Y2O3和 烟 台 大 学 硕 士 学 位 论 文 烟 台 大 学 硕 士 学 位 论 文 II Nd:YAG透明陶瓷
5、氧化物粉体要比尿素和草酸为沉淀剂好的多，当碳酸氢铵和氨水摩尔比 为 1:3 时制备的 Nd:Y2O3粉体经 1000C 热处理后，颗粒呈球状，晶界清晰，分布均匀， 颗粒平均直径约80nm。 关键词关键词 Gd2O3，Y2O3, YAG，粉体，沉淀，燃烧 烟 台 大 学 硕 士 学 位 论 文 烟 台 大 学 硕 士 学 位 论 文 III Abstract Rare earth oxide transparent ceramics have been paid much attention for excellent physical properties and superior optic
6、al characteristics. In comparison with single crystal and glass, the characteristics of rare earth oxide transparent ceramics offer several advantages, such as fabricated in large size easily, produced in mass with lower cost, and obtained higher output due to the high doping concentration. So it be
7、comes a competitive substitute material for single crystal and glass. The powders of (Nd:GdLa)2O3 and Er:Gd2O3 were prepared by co-precipitation method and sol-gel combustion method, by the comparing these two methods, we concluded that co-precipitation method was better than sol-gel combustion meth
8、od. Then the co-precipitation method was choosen to prepared the powders of Nd:Y2O3 and Nd:YAG with three different precipitants, in comparison, we thought multi-precipitant was the best. The process of heat disassembly, phase composition, morphology and purity of the powders were analyzed by TG-DTA
9、, XRD, SEM and FTIR, respectively. The structure of (Nd:GdLa)2O3 powders prepared with complex co-precipitation method was cubic after heat treatment with different temperatures, its grains were slice-like and uniform, having small-size and clear crystal boundary. With the increasing of heat treatme
10、nt temperature, the structure of (Nd:GdLa)2O3 powders prepared by sol-gel combustion method was changed from monoclinic to cubic. With 1100C heat treatment, (Nd:GdLa)2O3 powders prepared by sol-gel combustion were agglomerated, having a fluffy and porous morphology. Then with 1300C heat treatment, t
11、he powders were turned into cubic structure, its grains were spherical and uniform, having large-size and clear crystal boundary. Er:Gd2O3 powders having cubic phase were obtained by sol-gel combustion method when citric acid and EDTA were used as combination fuel. cubic phase was better than monocl
12、inic phase to the optical performance of powders in laser respect. But the powders also were fluffy, porous and agglomerated and its grains were irregular in morphology. Besides of oxalate being generated, Gd2O2CO3 was generated in the process of heat 烟 台 大 学 硕 士 学 位 论 文 烟 台 大 学 硕 士 学 位 论 文 IV treat
13、ment by oxalic acid co-precipitation method. The decomposition temperatures of oxalate and Gd2O2CO3 were about 401C and 642C. The grains prepared by acid co-precipitation method were in shape of flaky, having uniform size and clear crystal boundary. After 900C heat treatment, the average length of f
14、laky grains was about 1m, and the average thickness was about 20nm. The powders prepared by these two methods were easy to absorb CO2 and H2O to form CO32- on the surface of the grains OH-. By general comparison, it could be concluded that co-precipitation method was better than sol-gel combustion m
15、ethod to prepare rare earth oxide transparent laser ceramic powders. In co-precipitation method, the more strict reaction conditions were needed, if the urea was used as the precipitant. Under this strict reaction condition sulphate precipitate could be formed, which was difficultly decomposed in th
16、e process of heat treatment. If oxalic acid was used as precipitant, the powders grains prepared by co-precipitation method had large-size and irregular morphology. And Al3+ and Y3+ were difficultly precipitated by oxalate at the same time. By general comparison, it is concluded that multi-precipitant composed of NH4HCO3 and NH3H2O was better than urea and oxalic acid to prepare Nd:Y2O3 and Nd:YAG transparent laser ceramic powders. After 3h heat treatment at 1000C, the powders prep
