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纳米上转换环境功能材料制备研究

时间:2017-05-21 14:39来源:毕业论文
溶胶一凝胶法制备的样品在 900—950℃会发生晶型转变,而共沉淀法制备的样品在 800—900℃会发生晶型转变。同时,探讨了不同掺杂量对上转换荧光发光效果的影响

本课题分别采用溶胶一凝胶法和共沉淀法两种方法制备了 Y2-xPrxSiO5 上转换荧光粉。采用 X 射线衍射(XRD)、扫描电镜(SEM)、红外光谱、粒径仪、荧光光谱对制备的样品进行了表征。  探讨了不同煅烧温度对样品晶型的影响,XRD 数据结果表明:溶胶一凝胶法制备的样品在 900—950℃会发生晶型转变,而共沉淀法制备的样品在 800—900℃会发生晶型转变。同时,探讨了不同掺杂量对上转换荧光发光效果的影响,结果表明:当 Pr3+掺杂量为1%时荧光强度最强。而不同 Y:Si比对样品晶型的影响,结果表明当 Y:Si比为 2:1 时所得的样品为高纯度的 Y2SiO5。 采用荧光光谱对二种不同制备方法的荧光粉进行了表征,研究表明,溶胶—凝胶法制备的上转换荧光粉的荧光强度较共沉淀法制备荧光粉有较好的上转换发光效果。8953
关键词  上转换  纳米材料  共沉淀法  溶胶—凝胶法  Title: Title: Title: Title: Study on the preparation of up-conversion environmental
functional nano-materials  
Abstract Abstract Abstract Abstract: :: :      
In this work,Y2-xPrxSiO5 up-conversion phosphor has been prepared by sol-gel
process and co-precipitation method, respectively X-ray diffraction
(XRD), scanning electron microscopy (SEM), infrared spectroscopy (IR),
particle size analyzer, and fluorescence spectroscopy have been employed
to characterize the properties and performances of  Y2-xPrxSiO5 up-conversion
phosphor
The influence of different calcination temperature  on phase change was
studied, XRD data results showed that phase change  of the samples prepared
by the sol-gel method occurred  in the 900-950°C, and the impact of the
different ratio of Pr3+ to Y2SiO5 on photoluminescence (PL) intensity was  
also discussed, the results showed that 1% the doping amount of Pr
3+ had
the strongest fluorescence intensity; comparably,  phase transition of  
co-precipitation prepared samples  was occurred about in the 800-900°C;
different ratio of Y to Si can affect the phase of  the sample ,the results
studied on this showed that, when ratio of Y to Si  was 2:1, sample prepared
by this mean was of high purity Y2SiO5
The phosphors synthesized by the two kinds of different methods were
characterized by fluorescence spectroscopy (FS), the results showed that
the phosphors prepared by sol-gel method had a better photoluminescence
(PL) intensity than that prepared by co-precipitation method
 Keywords   Up-conversion  Nanometer Materials  Co-precipitation  
Sol—gel 目  次
 
目次     ..Ⅰ ⅠⅠ Ⅰ
1   引言..1
1.1  纳米上转换环境功能材料研究状..1
1.2 上转换材料的制备方法.4
1.3  上转换材料的应用6
1.4  本课题的研究目的7
1.5  本课题研究内容.8
2   溶胶—凝胶法制备样品及表征.9
2.1  试剂与仪器9
2.2  溶胶—凝胶法制备样品 Y2SiO5:Pr
3+
.9
2.3  样品 Y2SiO5:Pr
3+
的表征.9
2.4本章小结.14
3   共沉淀法制备样品及表征16
3.1 共沉淀法制备样品 Y2SiO5:Pr
3+
..16
3.2  样品 Y2SiO5:Pr
3+
的表征.16
3.3   本章小结.22
4   两种方法的比较.23
4.1  两种方法制得上转换荧光粉颗粒的粒径比较.23
4.2 两种方法中煅烧温度对晶型的影响比较23
4.3  两种方法制得上转换荧光粉荧光发光的比较23
结  论..25 纳米上转换环境功能材料制备研究:http://www.youerw.com/cailiao/lunwen_7504.html
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