介孔LaVO4：Eu3＋的制备和荧光性能

Preparation and Luminescence of Mesoporous LaVO_4:Eu^(3+)

以硝酸镧(La(NO3)3·6H2O)、硝酸铕(Eu(NO3)3·6H2O)、偏钒酸铵(NH4VO3)为原料,以十六烷基三甲基溴化铵(CTAB)为模板剂,用研磨-溶胶-凝胶法制备了三维蚯蚓状LaVO4:Eu3+介孔材料,并用XRD、XPS、TEM、BET、IR、FL等手段表征了材料的结构、形貌、比表面积、孔径分布及荧光性能。结果表明,在673 K焙烧所得的样品是四方锆石型结构的介孔材料,其比表面积达179.5 m2/g,平均孔径为2.56 nm,孔容积为0.115 m3/g,晶粒尺寸6.38 nm,表现出很强的红光发射(5D0→7F2)。适当提高焙烧温度能提高样品的红光发射,但焙烧温度过高(≥1273 K)则破坏材料介孔结构并使其荧光强度急剧降低。

Using cetyltrimethyl ammonium bromide （CTAB） as a template agent, a facile grinding sol- gel process was adopted to prepare earthworm-like LaVO,： Eu3~ mesoporous material with La（NO3）3. 6H20, Eu（NO3）3.6H20 and NH4VO3 as raw materials. The as-prepared samples were characterized by X- ray diffraction （XRD）, X-ray photoelectron energy spectrum （XPS）, transmission electron microscopy （TEM）, the BET specific surface area, infrared spectra （IR） and fluorescence spectra （FL）. It is found that the as-prepared LaVO4：Eu3＋ annealed at 673 K is a typical mesoporous materal with zircon structure of tetragonal phase （t）. The specific surface areas and the average pore diameter of the sample is about 179.5 m2/g and 2.56 nm, respectively, and its pore volume and grain size is 0.115 m3/g and 6.40 nm, re- spectively. The fluorescence results show that the mesoporous LaVO4： Eu3＊ exhibits a strong red emis- sion （5Dr→7F2）, and a suitable range of annealing temperature can improve its fluorescence properties, but more high annealing temperature （≥1273 K） can rapidly decrease its fluorescence intensity due to de- molishing the mesoporous structure of LaVO4：Eu3＋.