The Effect of Phase Structures on the Enhanced Red Upconversion Luminescence in NaLuF4:Yb-Er Nanocrystals.

In this work, α-NaLuF4:Yb,Er (NLF) nanocomposites (NCs) and β-NLF NCs with diameter about ~13 nm were fabricated by a high temperature decomposition reaction method. The effects of NLF structure on the enhanced red upconversion luminescence performance were investigated. Under 980 nm excitation from a laser diode, the α-NLF emitted dominant red UC emission. Furthermore, the possible energy transfer mechanism was proposed on the basis of our experimental results.