Browsing by Author "Quilty, CD"

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    Structural characterization and photoluminescence in the rare earth-free oxy-fluoride anti-perovskites Sr3−xBi2x/3AlO4F and Sr3−xBi2x/3GaO4F
    (Royal Society of Chemistry, 2017-03-01) Quilty, CD; Avdeev, M; Driskell, JD; Sullivan, E
    The activator Bi3+ has been successfully incorporated into the anti-perovskite oxy-fluoride host lattice Sr3MO4F (M = Al, Ga) to form rare earth-free phosphors of the composition Sr3−xBi2x/3AlO4F, 0 ≤ x ≤ 0.1, and Sr3−xBi2x/3GaO4F, 0 ≤ x ≤ 0.048. These phases absorb in the UV region (λex = 240–326 nm) and exhibit broad emission in the blue region of the visible spectrum (λem = 446.5–455 nm). The optimum compositions for maximum photoluminescent intensity were determined to be Sr2.976Bi0.016AlO4F and Sr2.976Bi0.016GaO4F before concentration quenching occurs. Full structural characterization based upon PXRD and NPD data were performed with DFT calculations suggesting that Bi3+ ions are preferentially incorporated on the ten coordinate Sr(1) site. © The Royal Society of Chemistry 2017
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    Synthesis and structural characterization of the vividly colored first row transition metal-containing oxyfluoride antiperovskites Sr3-xMnxMO4F and Sr3-xMnxMO4-αF1-δ (M = Al, Ga)
    (Elsevier, 2018-06-01) Quilty, CD; Avdeev, M; Sullivan, E
    Incorporation of dopant amounts of the divalent transition metal cation Mn2+ into the oxyfluoride material Sr3-xMnxMO4F (M  = Al, Ga; 0 ≤ x ≤ 0.1) yields green powders which vary in hue depending on the identity of M. Treatment of these phases with post-synthesis annealing under reducing conditions produces anion deficient phases according to Sr3-xMnxMO4-αF1-δ displaying vivid purple coloration. Intense colors are likely due to small amounts of Mn3+ on the tetrahedral M site. Full structural characterization based upon powder X-ray diffraction (PXRD), neutron powder diffraction (NPD), and thermogravimetric analysis (TGA) data are presented herein, demonstrating that the Sr3-xAxMO4F (A = Ca, Sr, Ba; M = Al, Ga) anti-perovskite structure can readily accommodate first row transition metals. © 2018 Elsevier Ltd.