Article,
Up-Conversion Luminescence of Er3+/Pr3+/Yb3+ Co-doped LaNbO4 Phosphors
JOURNAL OF ELECTRONIC MATERIALS, 49 (10): 6009-6015 (2020)
DOI: 10.1007/s11664-020-08329-x, Early Access Date = JUL 2020
Abstract
Er3+-Pr3+-Yb(3+)co-doped LaNbO4(LNO) phosphors were obtained by
solid-state reaction and their up-conversion properties have been
studied. The x-ray diffraction and Rietveld's refinement revealed no
evidence of significant structural changes or secondary phases in the
synthesized materials. According to the up-conversion measurements, the
observed emissions are due to Er(3+)ions which are present as
unintentional contaminant in the Pr(3+)doped and Pr3+-Yb(3+)co-doped
systems. The intensity of all the bands was enhanced with increasing
Yb(3+)concentration, and at 8%Yb(3+)a significant decrease of the green
and red emissions was found due to the presence of cross-relaxation
process between Er(3+)and Pr(3+)ions, mainly for green emissions because
of the back energy transfer mechanisms from Er(3+)to Yb3+. The
Commission Internationale de l'eclairage color coordinates of almost all
samples were located in the green region, while for the LNO: Pr
0.1%-Yb8% phosphor they were located in the blue region.
Red-Green-Blue phosphors were obtained from LaNbO4:
Pr3+/Er3+/Yb(3+)systems using the pair of activators Pr3+/Er(3+)which is
not commonly investigated in the literature.
