【摘要】 分别采用沉淀法和燃烧法制备了YAG:1%Eu3+纳米晶粉末,用XRD和TEM对样品进行了结构分析和形貌表征。室温光谱分析表明,其发射主峰位于590nm,来源于5 D0→7F1跃迁,另外来源于5 D0→7F4跃迁的709nm发射也较强。另外发现,燃烧法制备的样品在不同激发波长激发时,发射光谱峰形有显著变化。对沉淀法制备的纳米微粒经盐酸"浸蚀"表面修饰后,发现395nm激发时,676nm和693nm发光显著增强,而且693nm发射的激发谱中存在两个宽激发带。对表面修饰后样品的变温发光特性研究发现,随着温度的降低,676nm发射显著增强,而693nm发射显著减弱。对于上述现象通过纳米微粒的表面效应和缺陷态进行了分析和解释。更多还原

【Abstract】 YAG:1%Eu3+ nanocrystals were prepared by coprecipitation and combustion method,respectively.By using X-ray diffraction(XRD),transmission electron microscope(TEM)and fluorescence spectrometer,the structural,morphological and temperature dependent spectroscopic properties of YAG:1%Eu3+ nanocrystal were investigated.The results showed that the main emission peak of YAG:1%Eu3+ nanocrystal were at 590nm 609nm and 709nm,which were attributed to 5D0→7F1,7F2,7F4 transitions of Eu3+,respectively.For YAG:Eu3+ nanocrystal prepared by combustion method,the emission spectra changed obviously at different excitation wavelength.For surface treated YAG:Eu3+ nanocrystal prepared by coprecipitation method,the intensities of the 676nm and 693nm emissions increased remarkably at 395nm excitation,comparing with those at 235nm excitation,the intensity of 676nm emission increased and the intensity of 693nm emission decreased obviously with temperature decreasing.In addition,two wide excitation band for 693nm emission were found.All the results above mentioned were discussed on base of surface effect and local structural environment of Eu3+ ions.更多还原