LiY1axEux(MoO4)2 as a promising red-emitting phosphor of WLEDs synthesized by sol-gel process

A series of LiY1axEux(MoO4)2 redaemitting phosphors were synthesized by sol-gel technique. The phase impurity and spectroscopic properties were characterized by X-ray diffraction (XRD) and photo-luminescence (PL) spectra respectively. The effect of Eu3+ doping concentration, annealing temperature and the molar ratio of citric acid to the total metal cations (C: M) on the optical properties of the red phosphors were studied and optimized. It was found that all the samples could be excited efficiently by blue light (465 nm), which was well coincident with the emission of GaN based LED chips. The luminescent intensity reached maximum when annealing temperature was 750 [deg]C and Eu3+ doping concentration was 5% with C: M=3: 1.