title: Simultaneous morphology manipulation and upconversion luminescence enhancement of β-NaYF4:Yb3+/Er3+ microcrystals by simply tuning the KF dosage.
abstract: A strategy has been adopted for simultaneous morphology manipulation and upconversion luminescence enhancement of β-NaYF4:Yb(3+)/Er(3+) microcrystals by simply tuning the KF dosage. X-ray power diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and photoluminescence spectra (PL) were used to characterize the samples. The influence of molar ratio of KF to Y(3+) on the crystal phase and morphology has been systematically investigated and discussed. It is found that the molar ratio of KF to Y(3+) can strongly control the morphology of the as-synthesized β-NaYF4 samples because of the different capping effect of F(-) ions on the different crystal faces. The possible formation mechanism has been proposed on the basis of a series of time-dependent experiments. More importantly, the upconversion luminescence of β-NaYF4:Yb(3+)/Er(3+) was greatly enhanced by increasing the molar ratio of KF to RE(3+) (RE = Y, Yb, Er), which is attributed to the distortion of local crystal field symmetry around lanthanide ions through K(+) ions doping. This synthetic methodology is expected to provide a new strategy for simultaneous morphology control and remarkable upconversion luminescence enhancement of yttrium fluorides, which may be applicable for other rare earth fluorides.
authors.affiliation: 1] College of Materials &Environmental Engineering, Hangzhou Dianzi University, Hangzhou 310018, P. R. China [2] State Key Laboratory of Materials-Orient Chemical Engineering, College of Materials Science and Engineering, Nanjing Tech University, Nanjing 210009, P. R. China.
authors.forename: Mingye
authors.initials: M
authors.lastname: Ding
authors.affiliation: College of Materials &Environmental Engineering, Hangzhou Dianzi University, Hangzhou 310018, P. R. China.
authors.forename: Daqin
authors.initials: D
authors.lastname: Chen
authors.affiliation: College of Chemistry &Materials Engineering, Changshu Institute of Technology, Changshu 215500, Jiangsu, P. R. China.
authors.forename: Shilong
authors.initials: S
authors.lastname: Yin
authors.affiliation: College of Materials &Environmental Engineering, Hangzhou Dianzi University, Hangzhou 310018, P. R. China.
authors.forename: Zhenguo
authors.initials: Z
authors.lastname: Ji
authors.affiliation: College of Materials &Environmental Engineering, Hangzhou Dianzi University, Hangzhou 310018, P. R. China.
authors.forename: Jiasong
authors.initials: J
authors.lastname: Zhong
authors.affiliation: State Key Laboratory of Materials-Orient Chemical Engineering, College of Materials Science and Engineering, Nanjing Tech University, Nanjing 210009, P. R. China.
authors.forename: Yaru
authors.initials: Y
authors.lastname: Ni
authors.affiliation: State Key Laboratory of Materials-Orient Chemical Engineering, College of Materials Science and Engineering, Nanjing Tech University, Nanjing 210009, P. R. China.
authors.forename: Chunhua
authors.initials: C
authors.lastname: Lu
authors.affiliation: State Key Laboratory of Materials-Orient Chemical Engineering, College of Materials Science and Engineering, Nanjing Tech University, Nanjing 210009, P. R. China.
authors.forename: Zhongzi
authors.initials: Z
authors.lastname: Xu