【摘要】 在pH=1无模板条件下水热合成出直径为2～3μm的CePO4∶Tb核壳微球结构。其核壳表面由直径为20～30 nm、长度为200～300 nm的纳米棒组成。产物生长过程实验表明,首先形成球状团聚产物,然后一些颗粒在表面生长,由于奥斯瓦尔德熟化效应产物尺寸变大,最后表面上的部分颗粒消耗内部的核而外延生成一维纳米棒。CePO4∶Tb核壳微球的荧光性质和荧光寿命测试表明,当Tb3+摩尔分数为10%时,发射强度达到最大值,Tb3+浓度再增加其荧光发射强度由于浓度淬灭作用而迅速降低。更多还原

【Abstract】 Tb3+-doped CePO4 core-shell microspheres with diameter of 2~3 μm were hydrothermally synthesized at pH=1.0 without using any template or surfactant.It was observed that the shells of these spheres were composed by nanorods with a diameter of about 20~30 nm and lengths up to 200~300 nm.The time-dependent experiments were also carried out to investigate their growing process.Initially,aggregated spherical products were formed.Then,some particles grew on its surface.As a result of Ostwald ripening,the size of the product increased.Finally,at the expense of the cores inside the spheres,the surface of the product experienced a change from nanoparticles to nanorods.The luminescent properties and luminescence decay lifetimes of CePO4∶Tb core shell microspheres were performed,indicating that the strongest emission intensity was reached with 10% molar fraction of Tb3+ ions,which might be ascribed to the concentration quenching effect.更多还原