Synthesis of LaOF:Eu3+ Nanoparticles with Strong Luminescence Enhanced by Organic Ligands

LaOF:Eu 3+ nanoparticles were successfully prepared by annealing LaF 3 :Eu 3+ nanocrytsals which were capped with SiO 2 shell. The SiO 2 shell effectively prohibited the growth of LaF 3 :Eu 3+ nanocrystals during the annealing process, and it was etched off after annealing to obtain the LaOF:Eu 3+ nanoparticles. The LaOF:Eu 3+ nanoparticles had a size comparable to the original LaF 3 :Eu 3+ nanoparticles. Inorganic–organic hybrid nanoparticles of LaF 3 :Eu 3+ and LaOF:Eu 3+ nanoparticles with thenoyltrifluoroacetone (TTA) ligands were prepared. Strong luminescence as a result of the energy transfer from the TTA organic ligands to the LaF 3 :Eu 3+ and LaOF:Eu 3+ nanoparticles was observed. The LaOF:Eu 3+ -based hybrid nanoparticles exhibited stronger luminescence intensity and broader excitation spectral range than the LaF 3 :Eu 3+ -based hybrid nanoparticles. Effect of the content of TTA ligands on the luminescence of the LaOF:Eu 3+ nanoparticles was investigated in detail.