An efficient red phosphor LuNb2VO9:Eu3+ with broadband excitation and abnormal thermal quenching properties for personal identification, security ink, and w-LEDs

A series of red-emitting phosphors LuNb2VO9 (LNV):xEu3+ (x = 0.5–45 mol%) were successfully obtained through the high-temperature solid-state reaction. The structure, phase purity, photoluminescence spectra, thermal stability properties, and color purity of the obtained phosphors were systematically examined. The LNV:Eu3+ phosphor exhibits broadband excitation due to the O2-→Eu3+ and O2-→V5+ charge transfer. The LNV:Eu3+ phosphor excited at 316 nm shows four emission peaks at 595, 615, 619, and 699 nm, corresponding to electron transitions from the 5D0 level to the 7F1, 7F2, 7F3 and 7F4 levels. The optimal doped concentration of LNV:xEu3+ is x = 10 mol%. The quenching mechanism is attributed to the nearest neighbor ion interaction. Furthermore, the prepared phosphor exhibits good thermal stability and remarkable activation energy Ea (0.74 eV). In addition, LNV:Eu3+@oleic acid (OA) readily exhibits the level I-III characteristics of fingerprints and the detailed characteristics of lip lines. The successful utilization of LNV:Eu3+ in anti-counterfeiting ink has yielded impressive results. The Commission International de L′ Eclairage (CIE) coordinate of the prepared white light-emitting diode (w-LED) in this study is (0.331, 0.367), accompanied by a color rendering index (Ra) of up to 95. Notably, the results of these experiments indicate that LNV:Eu3+ phosphor possesses exceptional luminescence properties and holds promising applications. •LuNb2VO9:Eu3+ phosphors were synthesized via solid-state reaction.•The phosphors exhibit good thermal stability and high color purity.•The phosphors perform well in visualizing latent fingerprints and lip prints.•The fabricated w-LED has a high color rendering index (Ra = 95).