在不加任何表面活性剂的条件下,通过水热法直接合成了LaPO4:Eu3+纳米棒,并采用溶胶-凝胶法在其表面修饰了一层SiO2,得到了LaPO4:Eu3+@SiO2纳米棒.XRD分析表明,样品包覆前后均属于单斜晶系的独居石型的LaPO4.FTIR分析表明,LaPO4:Eu3+粒子与SiO2是以化学键的形式结合在一起.由TEM照片可见,所得LaPO4:Eu3+样品为直径约20 nm、长度达300～500nm的长径比较大的纳米棒.通过改变TEOS的加入量得到了不同包覆层厚度的LaPO4:Eu3+@SiO2纳米棒.荧光光谱分析表明:以259 nm作为激发波长,LaPO4:Eu3+发光纳米棒的主发射峰位于591 nm,为Eu3+的特征橙红光发射,归属于Eu3+的5Do→7F1跃迁.随着SiO2包覆层厚度的增加,样品的激发光谱和发射光谱的强度逐渐减弱,峰形和谱峰的位置没有明显的变化.%LaPO4: Eu3+ luminescence nanorods were prepared via a hydrothermal method without any surfactants, then an uniform SiO2 layer was coated on the surface of LaPO4: Eu3+ nanorods by sol-gel method. At lasts LaPO4: Eu3+@ SiO2 core-shell structural luminescence nanorods were achieved. XRD patterns show that the uncoated and coated samples are all monclinic LaPO4 crystals. FTIR spectra indicate that LaPO4: Eu3+ is linked with SiO2 by chemical bond. TEM images reveal that the LaPO4: Eu3+ samples are one-dimensional nanorods with a diameter of 20 nm and a length of 300 ～ 500 nm. The coating thickness of SiO2 can be controlled by the concentration of TEOS. The results of photoluminescence properties show that the main emission peak of LaPO4: Eu3+ nanorods is near 591 nm, which is the characteristic orange red light corresponding to 5D0→7F1 transition of Eu3+ under 259 nm excitation. The PL intensity of the samples become weak with the increasing of the coating thickness, but the shape and the position of the peaks are not changed.
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