六方相LaOF纳米体系中Sm3+/Eu3+的能量转移效应

为了探讨Sm3+/Eu3+共掺体系的荧光光谱特性和能量转移机理,采用水热-烧结法制备了Sm3+/Eu3+共掺LaOF纳米晶体颗粒,并用X射线衍射和透射电子显微镜对纳米晶体颗粒进行了表征.结果显示,所制备的纳米晶体颗粒呈六方相,均匀性和分散性良好,平均粒径为70 nm左右.通过442 nm连续光激发,在六方相LaOF:Sm3+/Eu3+纳米体系中实现了Sm3+离子向Eu3+离子的能量转移,观测到了因能量转移效应而产生的Eu3+离子5D0能级的荧光发射谱线.光谱学研究发现,能量转移源于Sm3+离子4G5/2能级向Eu3+离子5D0能级的弛豫过程,并且随着受主离子Eu3+浓度的增加,能量转移效率也随之提高.

Energy Transfer Effect of Sm3+/Eu3+ Co-doped in LaOF Nanocrystals System with Hexagonal Phase

In order to investigate the mechanism of energy transfer and fluorescence properties of Sm3+/Eu3+ co-doped system,the samples of Sm3+/Eu3+co-doped in LaOF nanocrystals were synthesized by using a hydrothermal-sintering technique.The characterization results of XRD and TEM show that the structure of the nanocrystals is hexagonal,and its size is about 70 nm.Using 442 nm laser to pump the LaOF:Sm3+/Eu3+ nanocrystals,the energy transfer effect from Sm3+ ions to Eu3+ ions was completed,and the fluorescence emissions originating from the 5D0 level of Eu3+ were observed.The luminescence properties of the LaOF:Sm3+/Eu3+ nanocrystals system were analyzed with a spectroscopic method.It was found that the energy transfer results from the relaxation from the 4G5/2 state of Sm3+ ions to the 5D0 state of Eu3+ ions,and the efficiency of the energy transfer increases with the increase of the concentration of Eu3+ ions.