本科论文.doc

1 微乳液法制备长余辉发光材料 SrAl 2O 4 :Eu 2+ ,Dy 3+ 摘要本论文评述了铝酸盐长余辉材料的特点及优点, 描述了铝酸盐长余辉发光材料长余辉机理和发光模型, 指出长余辉机理来自陷阱对空穴的俘获与缓慢释放, 还介绍了合成纳米材料的重要方法---微乳液法,描述了微乳液的概念及微乳化反应器的原理、形成与结构,并进一步阐述了微乳液在纳米材料制备领域的应用。本文采用了化学沉淀法和微乳液法两种方法制备长余辉发光材料 SrAl 2O 4 :Eu 2+ ,Dy 3+ 的超细纳米微粒。其中,化学沉淀法采用氨水作沉淀剂,形成不溶性氢氧化物、水合氧化物或盐类从溶液中析出,获得符合要求的共沉淀。本论文的重点是应用微乳液法制备,用混合非离子表面活性剂吐温-60 和司藩-20 , 以异戊醇作助表面活性剂,环己烷作为油相,混合离子溶液作为水相,制成 W/O 型微乳液,反应产物经烘干,预烧后,在弱还原气氛( H 2—N 2)下控制温度煅烧制得长余辉发光材料 SrAl 2O 4 :Eu 2+ ,Dy 3+。实验通过不断改变混合非离子表面活性剂的质量比,助表面活性剂的用量,混合离子浓度大小,反应期间溶液的 PH 值等实验条件观察其对微乳液性质的影响。在弱还原气氛( H 2—N 2)下观察不同的煅烧温度对长余辉发光材料 SrAl 2O 4 :Eu 2+ ,Dy 3+ 的发光性能影响。通过利用红外光谱仪和 X- 射线分析仪,对纳米粒子有机修饰和晶型结构进行了初步探讨。结果表明, 在用环己烷为油相, 异戊醇为助表面活性剂, 吐温-60 和司藩-20 为表面活性剂组成的微乳体系中, 它们较好的配比是环己烷: 异戊醇: 水相: 吐温-60: 司藩-20 为 150ml : 6ml:10ml:: 。 1100 ℃发光材料的发光性能较好。关键词铝酸盐蓄光材料长余辉微乳液纳米材料 2 Preparation of long afterglow luminescence materials SrAl 2O 4 :Eu 2+ ,Dy 3+ by microemulsion method Abstract In this paper We employ chemical settling method and microemulsion method to prepare nanometer particle of SrAl 2O 4 :Eu 2+ ,Dy 3+ which is long-afterglow phosphor Chemical settling method employ ammonia as precipitant to prepare in soluble hydroxide, hydrate oxide or salt which can be separated from solution ,to obtain co-precipitation . The important point of this article isby using microemulsion method to prepare long-afterglow phosphor .T his article employ non-ionic surface active agent and use cyclohexane as oil phase and use mixed – ion as water phase to prepare W/O kind of microemulsion . In nitrogen and hydrogen environment we prepare nanometer particle of SrAl 2O 4 :Eu 2+ ,Dy 3+ .The effect of the mass ratio of mixed non-ionic surface active agent, the mass of concentration of mixed-ion, and the solution pH on the microemulsion properties were investigated , this reaction consumed and the phosphor of solution so that we know it effluence on property of long-afterglow phosphor of product at some degree are observed after calcinations at different tempe