Photoluminescence properties of NaSr(P, V)O4:Eu3+ phosphors

Eu3+ activated NaSr(P,V)O4 phosphors have been synthesized using solid state reaction method and further characterized for their structure and optical properties using different techniques such as X-ray diffraction, scanning electron microscopy, photolumniscenec excitation, emission, and chromaticity coorrdinate analysis, etc. Material shows a broad excitation peak (monitored for lambda(ems) = 613 nm) lying in the 300-360 nm region and gives intense transitions (lambda(exc) = 320 nm) namely 5D0 --> 7F1 at 590 nm, 5D0 --> 7F2 at 613 nm, 5D0 --> 7F3 at 650 nm, and 5D0 --> 7F4 at 700 nm due to Eu3+ ion. Our results show that replacement of the PO4(3-) ions with isomorphic VO4(3-) ions improves the structural stability and the overall intensity of the emission. The maxium emission intensity is achieved for the NaSr(P0.4, V0.6)O4:Eu3+ phosphor. An estimated increase of an order is attained for the NaSr(P0.4, V0.6)O4:Eu3+ phosphor as compared to NaSrPO4:Eu3+ or NaSrVO4:Eu3+ phosphor. The chromaticity coordinate of the phosphor (0.68, 0.31) lies well within the red region and suggest that the material could be an alternative red phosphor for lighting and display applications.