title: One-step synthesis of water-soluble hexagonal NaScF4:Yb/Er nanocrystals with intense red emission.
abstract: Water-soluble hexagonal NaScF4:Yb/Er nanocrystals have been directly synthesized via a facile one-step hydrothermal route. The as-prepared nanocrystals were monodisperse and could form stable colloidal solutions in polar solvents, such as water and ethanol. The novel NaScF4:Yb/Er nanocrystals exhibited intrinsic intense red upconversion emission, in contrast to other lanthanide-doped fluoride nanocrystals. Remarkably, the upconversion emission intensity was enhanced ∼6.8 times through the coating of an active-shell (containing Yb(3+)) surrounding the NaScF4:Yb/Er core nanocrystals, owing to surface passivation effect and efficient energy transfer from Yb(3+) ions in both the core and the shell to Er(3+) ions. These water-soluble hexagonal NaScF4:Yb/Er nanocrystals with intense red emission are ideal for a variety of in vitro and in vivo biological imaging applications.
authors.affiliation: State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun 130022, China. fengj@ciac.jl.cn hongjie@ciac.jl.cn.
authors.forename: Min
authors.initials: M
authors.lastname: Pang
authors.forename: Xuesong
authors.initials: X
authors.lastname: Zhai
authors.forename: Jing
authors.initials: J
authors.lastname: Feng
authors.forename: Shuyan
authors.initials: S
authors.lastname: Song
authors.forename: Ruiping
authors.initials: R
authors.lastname: Deng
authors.forename: Zhuo
authors.initials: Z
authors.lastname: Wang
authors.forename: Shuang
authors.initials: S
authors.lastname: Yao
authors.forename: Xin
authors.initials: X
authors.lastname: Ge
authors.forename: Hongjie
authors.initials: H
authors.lastname: Zhang
mesh_terms: D004871:Erbium / Q000737:chemistry*; D005459:Fluorides / Q000737:chemistry*; D049449:Luminescence; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D012538:Scandium / Q000737:chemistry; D012995:Solubility; D014867:Water / Q000737:chemistry; D015018:Ytterbium / Q000737:chemistry*
chemical_list: D014867:Water; D004871:Erbium; D015018:Ytterbium; D005459:Fluorides; D012538:Scandium