Controllable synthesis and luminescence property of LnPO_4 (Ln = La, Gd, Y) nanocrystals

摘要

Lanthanide orthophosphate LnPO_4 (Ln = La, Gd, Y) nanocrystals with different crystalline structures and morphologies were synthesized successfully by a hydrothermal method under mild conditions. The obtained LaPO_4 have a monoclinic or hexagonal structure with varying the temperature. However, as to GdPO_4 and YPO_4, the temperature has no obvious effect on their structures. By tuning the amount of cetyltrimethylammonium bromide (CTAB), the morphology and size of all samples can be controlled easily and effectively. Noticeably, the structure of YPO_4 can also be controlled by using the CTAB. A systematic study of the photoluminescence in Ln~(3+)-doped lanthanide phosphates shows that the luminescent properties of these nanophosphors are strongly dependent on their crystal structures and morphologies.