Photoluminescent and crystalline properties of Y3−xAl5O12:Cex3+ phosphor nanofibers prepared by electrospinning

Abstract

Cerium-doped yttrium aluminum garnet (YAG:Ce3+; Y3−xAl5O12:Cex3+) phosphor nanofibers were successfully prepared using an electrospinning method followed by a heating process. Aluminum nitrate nonahydrate, yttrium nitrate hexahydrate, and cerium nitrate hexahydrate dissolved in dimethylformadide, poly(vinyl pyrrolidone), and ethanol comprised the precursor. The precursor was electrospun under atmospheric conditions to obtain the as-prepared fibers, which consisted of salts and the polymer composite. The as-prepared fibers were then heated to remove the polymer and to obtain the YAG:Ce3+ crystalline fibers. The morphology of the final fibers was homogeneous; the fibers were approximately 300 nm in diameter and several centimeters in length. The photoluminescence (PL) and crystalline properties of the fibers were studied as a function of both the doping fraction (0.005≤x≤0.4) and the heating temperature (900–1400 °C). High heating temperatures resulted in a high degree of crystallinity, crystallites that ranged from 20 to 55 nm in size, and enhanced PL intensity. A doping concentration of 1% (x=0.01) gave the highest PL intensity under excitation at 470 nm. The PL spectra were centered at 530 nm due to the transition from the 5d state to the 4f state (A21g→F25/2 and A21g→F27/2).