Facile synthesis, morphology and tunable photoluminescence properties of BaMgF4:Ce3+/Tb3+/Eu3+ phosphors

Abstract

A series of BaMgF₄:Ce³⁺/Tb³⁺/Eu³⁺ phosphors were successfully prepared via a facile hydrothermal process. X-ray diffraction (XRD), energy dispersive spectrometry (EDS), scanning electron microscopy (SEM), n-UV–UV-vis photoluminescence (PL) and fluorescence decays were employed to investigate the structure, composition, morphology, luminescence properties and energy transfer processes. The as-prepared BaMgF₄ phosphors exhibit a rod-like morphology and the size of the product can be effectively regulated by changing the amount of NH₄F in the original solution. Under n-UV–UV light excitation, the Ce³⁺, Tb³⁺ and Eu³⁺ singly-doped BaMgF₄ phosphors all show good characteristic luminescence; the Ce³⁺–Tb³⁺ and Tb³⁺–Eu³⁺ co-doped BaMgF₄ phosphors both show tunable emission colors from blue (green) to green (orange-red) because of the energy transfer of Ce³⁺ → Tb³⁺ and Tb³⁺ → Eu³⁺, respectively. Moreover, the efficient energy transfer from Ce³⁺ (Tb³⁺) to Tb³⁺ (Eu³⁺) ions in the co-doped samples was confirmed by investigating the excitation/emission spectra and decay lifetimes. The results indicate that the phosphors may be potentially used as single-component multi-color phosphors for white light-emitting diodes.