Size-dependence of LaF3:Eu3+ nanocrystals on Eu3+ photo-luminescence intensity

Size-dependence of Eu3+-doped LaF3 nanocrystals on the 5D0-7FJ photoluminescence intensity was investigated, where LaF3:Eu3+ nanocrystals were prepared through a hydrothermal route with a cationic surfactant cetyltrimethylammonium bromide (CTAB) as size-controlled agent and by post-annealing at an appropriate temperature at N2 atmosphere. It was found that LaF3:Eu3+ obtained was in hexagonal structure with space group P3c1 and had good crystalinity. When LaF3:Eu3+ nanocrystals were synthesized with 0.006 mol/L CTAB the average particle size was maximized to be 25.4 nm and the luminescence intensity was 1.5 times higher than that prepared without CTAB or with more CTAB concentration. The mechanism of the particle growth was also discussed in this paper.