Synthesis and optical properties of blue-light excitable BaBiNaTeO6:Eu3+ red-emitting bismuthate phosphors for white LEDs

A series of red-luminescence bismuthate phosphors of double perovskite BaBiNaTeO 6 doped with trivalent europium (Eu 3+ ) were prepared by the solid-state diffusion method. The crystal structure and phase purity of the phosphors were analyzed. The photoluminescence (PL) properties of BaBiNaTeO 6 :Eu 3+ were studied in detail. Upon blue light (466 nm) excitation, the powders showed brilliant red light at around 619 nm, and it was attributed to the electric dipole (ED) 5 D 0  →  7 F 2 transition of Eu 3+ . The optimal dopant concentration ( x ) of the as-prepared phosphor was x  = 0.60 mol and the concentration quenching mechanism was evaluated as the electric quadrupole–quadrupole interaction. The BaBiNaTeO 6 :Eu 3+ exhibited good thermal stability and the corresponding activation energy ( E a ) was obtained to be 0.27 eV. The chromaticity points of phosphors were near the edge of the red region of the Commission Internationale De L’Eclairage (CIE) 1931 chromaticity diagram. As-prepared white LED based on the GaN blue chip exhibited relatively low correlated color temperature (CCT) of 5042.5 K and high color rendering index (CRI) of 91.6. All characterizations suggest that these double perovskite BaBiNaTeO 6 :Eu 3+ red-emitting phosphors have promising applications in illumination and display field based on blue LEDs.