Hydrothermal synthesis and optical properties of Tb/Ce doped barium lithium fluoride

Phase-pure Ce-/Tb-doped and co-doped barium lithium fluoride (BaLiF3) phosphors are synthesized by hydrothermal techniques at 200 °C for 5 days. The crystal structure, particle size, morphologies, the energy band structure and photoluminescence properties of the as-synthesized products are investigated by X-ray powder diffraction (XRD), environment scanning electron microscopy (ESEM), X-ray photoelectron spectroscopy (XPS) and photoluminescence spectroscopy (PL). In the co-doping of Ce3+ and Tb3+ in BaLiF3 phosphors, there is the excitation band of Ce3+ exclusively in the excitation spectrum, while the characteristic emission from 5D4 → 7FJ (J = 6, 5, 4, 3) of Tb3+ can only be observed in the emission spectrum. Especially the emission peak ascribed to Tb3+ ions transition from 5D4 → 7F5 strengthens greatly due to an effective energy transfer from Ce3+ to Tb3+ in co-doped system of BaLiF3. These results suggest that the phosphors of BaLiF3:Ce3+, Tb3+ would become promising green-emitting fluorescent materials.

► A facile preparation method of phosphors of BaLiF3 doped Tb or/and Ce. ► Their structural characterization. ► Their luminescent properties of the rare-earth ion-doped BaLiF3. ► The discussion of energy transfer mechanism from Ce3+ to Tb3+ in the host.