Structure and tunable blue-white-red luminescence of Eu2+/Eu3+-doped Na5Al(PO4)2F2 single-phase phosphor

• A new fluorophosphate phosphor was developed by modified solid-state reaction.
• The structural XRD refinement was successfully performed.
• The host accommodates two kinds of Eu-centers, i.e., Eu3+ and Eu2+.
• The luminescence color could shift in blue-white-red under different excitation.

Eu2+/Eu3+-doped fluorophosphate Na5Al(PO4)2F2 was synthesized by the high-temperature solid-state reaction. The structural XRD refinement was used to investigate the phase formation and structure. The photoluminescence (PL) excitation and emission spectra were measured. The host accommodates two kinds of Eu-centers in the lattices, i.e., Eu3+ and Eu2+, which were confirmed by the emission spectra and decay curves. Under the excitation of UV and near-UV light, the broad emission peaked at 420 nm and 530 nm from the 4f65d–4f7 transition of Eu2+ and narrow peaks at 592 nm, 615 nm from the 4f–4f transitions of Eu3+ ions were detected. The luminescence color could shift from blue to white and red by mixing the luminescence from the coexistence of Eu2+/Eu3+ ions in the single-phase phosphor.