Influence of Eu~(3+) ions in Na_(0.5)La_(0.5)MoO_4: structural and optical investigation

摘要

Intense red-emitting phosphor Na_(0.5)La_(0.5-x) MoO_4:xEu~(3+) (x = 0.02, 0.04, 0.06, 0.08, 0.10 mol of Eu~(3+)) was prepared at 900 ℃ for 3 h using conventional solid-state reaction method. Crystal structure and phase purity of the phosphor were identified using X-ray diffraction analysis. The morphology and composition of the materials were examined by scanning electron microscope, energy dispersive X-ray spectrum, and X-ray photoelectron spectroscopy, respectively. The diffuse reflectance spectra of Na_(0.5)La_(0.5-x)MoO_4:xEu~(3+) showing a significant shift in the band gap (0.14 eV) was observed due to increase in doping concentration of Eu~(3+). Photoluminescence and decay time (t) study on Na_(0.5)La_(0.5-x)MoO_4:xEu~(3+) showed strong red emission upon UV illumination, and this implied potential application in the field of luminescent displays.