熔盐法制备KSm(MoO4)2粉体艺参数的研究毕业论文.docVIP

2014 届毕业设计（论文） 题 目：熔盐法制备KSm(MoO4)2 粉体工艺参数的研究 专 业 复合材料与工程 班 级：复材1001 姓 名： 指导老师： 起讫日期：2013.12-2014.6 2014 年 6 月 摘 要 白光LED作为第四代照明光源与传统照明相比，具有节能、环保、寿命长、响应速度快等诸多优点。稀土钼酸盐材料广泛光材料制备方法，沉淀法、等本文采用熔盐法，以KCl或KBr为熔盐制备KSm(MoO4)2粉体，研究了煅烧温度、保温时间、熔盐掺量、熔盐种类及升温速率对合成的KSm(MoO4)2粉体的结构及形貌的影响。采用X线衍射仪（XRD）和扫描电子显微镜（SEM）对产物的形貌和结构进行了表征。研究结果表明：在40 wt% KCl熔盐介质中，当反应温度为750 ℃，保温时间为2 h，升温速率为3 ℃/min条件下，合成产物为形貌规整、尺寸均一的八面体状KSm(MoO4)2微晶。对KSm(MoO4)2粉体进行了室温光致发光光谱(PL)性能测试，结果表明：在404 nm波长激发下，发射光谱在563、601、646 nm处出现发射峰，这些发射峰由Sm3+的4G5/2→6H5/2、4G5/2→6H7/2和4G5/2→6H9/2电子跃迁组成，说明KSm(MoO4)2可以在近紫外光激发下发出橙红色的光。 KSm(MoO4)2红色荧光粉 熔盐法 钼酸盐 发光性能 ABSTRACT Compared with traditional lighting, white light emitting diode (LED) as the fourth generation of lighting source possesses such excellent performance as low power consumption, no pollution, long lifetime and fast response time, and so on. Rare-earth molybdenum acid salt materials are widely used in Luminescence materials. There are many methods for preparing these materials, such as high-temperature solid phase synthesis method, precipitation method, sol-gel method and molten salt method. This paper adopted the molten salt method to prepare KSm(MoO4)2 microcrystalline with KCl or KBr as the molten salt media. The effects of calcination temperature, holding time, types of molten salt and heating rate on the structure and morphology of KSm(MoO4)2 were investigated. The morphology and structure of the as-prepared products were characterized by X-ray powder diffractometer (XRD) and scanning electron microscopy (SEM). The results showed that the more uniform size octahedral-like KSm(MoO4)2 products were obtained at 750 ℃ for 2 h with the heating rate of 3 ℃/min in 40 wt% KCl mediun. The room temperature photoluminescence (PL) spectra showed that the emission spectra of all KSm(MoO4)2 products have three emission peaks which located at around 563, 601 and 646 nm ,these emission peaks correspond to 4G5/2→6H5/2、4G5/2→6H7/2 and