CaYGaO4; a fully ordered novel olivine type gallate

Eu2+luminescence in CaYGaO4olivine: a new efficient red phosphor for warm illumination

“…The obtained cell volume ( V ) of the phosphor is 395.710 Å 3 , slightly larger than that of the starting model ( V = 393.86 Å 3 ). 40 This is due to the replacement of the six-fold coordinated Ca 2+ ion (ion radius, R = 1.00 Å) by an Eu 2+ ion ( R = 1.17 Å). XPS survey scans in the range of 0–1350 eV of the Ca 0.98 YGaO 4 :0.02Eu 2+ phosphor show that the spectra have sharp lines corresponding to Ca, Y, Ga, and O (Fig.…”

“…1b). 40 It is assumed that the Eu 2+ ion tends to occupy the octahedral Ca 2+ site in view of its ionic radius and valence states compared to those of the Ca 2+ . 32,41,42 Powder XRD measurements on Ca 1Àx YGaO 4 :xEu 2+ (x = 0.005-0.04) show that the Bragg reflection peaks of the phosphors can be well indexed to orthorhombic CaYGaO 4 (Fig.…”