Structural characterization and photoluminescence in the rare earth-free oxy-fluoride anti-perovskites Sr 3-x Bi 2x/3 AlO 4 F and Sr 3-x Bi 2x/3 GaO 4 F

The activator Bi has been successfully incorporated into the anti-perovskite oxy-fluoride host lattice Sr MO F (M = Al, Ga) to form rare earth-free phosphors of the composition Sr Bi AlO F, 0 ≤ x ≤ 0.1, and Sr Bi GaO F, 0 ≤ x ≤ 0.048. These phases absorb in the UV region (λ = 240-326 nm) and exhibit broad emission in the blue region of the visible spectrum (λ = 446.5-455 nm). The optimum compositions for maximum photoluminescent intensity were determined to be Sr Bi AlO F and Sr Bi GaO F before concentration quenching occurs. Full structural characterization based upon PXRD and NPD data were performed with DFT calculations suggesting that Bi ions are preferentially incorporated on the ten coordinate Sr(1) site.