Efficient Sensitization of Eu3+ Emission by Tb3+ in Ba3La(PO4)3 under VUV-UV Excitation: Energy Transfer and Tunable Emission

The work presents the VUV-UV vis photoluminescence of Ba3La(PO4)(3):Ln(3+) (Ln = Tb, Eu) prepared by a high. temperature solid-state reaction route. The excitation and emission spectra, the fluorescence decays, and the time-resolved emission spectra were measured and discussed in detail. The results reveal that Tb3+ can efficiently transfer excitation energy to Eu3+ via its 5d and 4f states and therefore sensitizes Eu3+ emission under VUV-UV excitation, resulting in tunable emission in a large color gamut.