Synthesis, Characterization and Spectral Studies of Novel Eu3+ Based Phosphors and its Solid Solutions

Abstract

Tungstate and molybdate based metal oxides with substituted Eu3+ based phosphors are promising red emitting phosphor materials for white LEDs. In the present research, a series of novel red phosphors including La2GdBWO9 as a host and doped La2Gd0.9Eu0.1BW1-xMoxO9 (x = 0 – 0.4, insteps of 0.1) samples were prepared by the conventional solid state reaction. The phase formation and transformation of the synthesized compositions was investigated by powder X-ray diffraction, DRS studies and photoluminescence properties were studied as a function of the Mo/W ratio. All the compositions show broad charge transfer (CT) band due to CT from O to W/Mo and red emission due to Eu3+ ions. Eu3+ substituted compositions show high red emission intensity under NUV/blue ray excitation as well as the emission of the phosphor shows very good CIE (Commission Internationale de l’Eclairage) chromaticity coordinates (x = 0.6647, y = 0.3349). Band gap of La2Gd0.9Eu0.1BW1-xMoxO9 (x = 0 – 0.3, insteps of 0.1) becomes narrower than that of host La2GdBWO9 by introducing Mo6+. The obtained results are reveals that the investigated phosphors are potential phosphors for LEDs.