title: Enhanced Red Upconversion Luminescence in Yb-Er Codoped NaYF4 Nanocrystals.
abstract: In this work the effects of NaYF4:Yb,Er (NYE) structure on the enhanced red upconversion luminescence (UC) was investigated. α-NYE nanocrystals (NCs) and β-NYE NCs were fabricated by a high temperature decomposition reaction method. The prepared NCs were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and photoluminescence (PL) spectroscopy. The results show that the red UC luminescence of α-NYE NCs is significantly enhanced compared with that of β-NYE. Furthermore, a possible energy transfer mechanism was proposed on the basis of our experimental results.
authors.forename: Weiye
authors.initials: W
authors.lastname: Song
authors.forename: Xueqing
authors.initials: X
authors.lastname: Bi
authors.forename: Xingyuan
authors.initials: X
authors.lastname: Guo
authors.forename: Shushen
authors.initials: S
authors.lastname: Liu
authors.forename: Weiping
authors.initials: W
authors.lastname: Qin