The blue phosphor Sr2CeO4 synthesized by Pechini's method

Blue emitters are very attractive research subjects because of their possib le industrial applications as phosphors for field emission displays. Recent ly, a blue phosphor, Sr2CeO4, was identified by a combinatorial materials s ynthesis technique. This material was further synthesized using the chemica l coprecipitation method and the decomposition of acetates, carbonates and oxalates in a tedious procedure. In this work, we present the use of Pechin i's method as an alternative for the synthesis of this promising material. When the precursor, (Sr/Ce) polymer citrate-ethylene glycol, was fired at 8 50 degreesC for 2 h, a mixture of Sre(2)CeO(4) and SrCeO3 (inactive) was ob tained, whereas the amount of Sr2CeO4 was increased by further heating at 1 100 degreesC for 2 h in an oxygen atmosphere, as shown by the diffraction p attern. The excitation spectra present two broad bands with maxima at 294 a nd 344 nm and the emission spectrum has a broad band (half width similar to 80 nm) centered at similar to 475 nm. The unusually long lifetime of the c ompound fired at 1100 degreesC of similar to0.04 ms is in good agreement wi th literature data. In conclusion, the blue phosphor material Sr2CeO4 synth esized at 1100 degreesC in an oxygen flux has comparable or even better emi tter properties than that prepared over several days and/or at higher tempe ratures. The method is very attractive for industrial purposes. (C) 2001 El sevier Science B.V. All rights reserved.