Preparation of SrR2O4:Eu3+ (R=Y Lu) phosphor and its photolumineseence properties

In this work, we present a novel approach for synthesis of europium (III)-doped SrR2O4:Eu3+ (R=Y, Lu) superfine phosphor with a precursor prepared in water-in-oil microemulsion. The precursor of oxalates formed in a reaction between Sr(NO3)(2)-Y(NO3)(3)(Lu(NO3)(3))-Eu(NO3)(3) and H2C2O4 in reverse microemulsions composed of OP-10, iso-pentanol, cyclohexane and water. X-ray diffraction results confirmed the formation of SrY2O4:Eu3+ and SrLu2O4:Eu3+ at 1000 degrees C and 900 degrees C respectively. FE-SEM images showed the superfine powder of SrR2O4:Eu3+ has a rugby-like shape and a diameter of 70-100 nm. Upon excitation with 257-272 nm UV light, all the SrR2O4:Eu3+ (R=Y, Lu) powders show bright red emission due to the 4f-4f transitions of Eu3+ ions, and the highest photoluminescence intensity at 618 nm for SrY2O4:Eu3+ and 615 nm for SrLu2O4:Eu3+ was found at a content of about 9 mol% Eu3+ and 6 mol% Eu3+ respectively. Splitting of the D-5(0)-> F-7(0) and D-5(0)-> F-7(1) emission transitions revealed that the Eu3+ ions occupied two nonequivalent sites in the crystalline lattice by substituting Y3+ or Lu3+ ions. (c) 2005 Elsevier B.V. All rights reserved.