Synthesis and Upconversion Emission Properties of Green Emitting Y4MoO9: Er3+/Yb3+ Phosphor

Yttrium molybdate (Y4MoO9) phosphor co-doped with Er3+/Yb3+ has been prepared by co-precipitation method and its upconversion emission property is studied. The structural investigations have been carried out on the basis of X-ray diffraction, Fourier transform infrared spectroscopy and field emission scanning electron microscopy analysis. The X-ray diffraction pattern suggests that the synthesized Y4MoO9 phosphor has a tetragonal phase structure. The Y4MoO9 phosphor doped with Er3+ ions shows two prominent upconversion emission bands at 530 nm and 552 nm in green region upon 980 nm diode laser excitation. The emission intensity of these upconversion emission bands has been enhanced by several folds through Yb3+ co-doping. The red emission band at 656 nm is found to be negligible in singly Er3+ as well as in Er3+/Yb3+ doped sample. The pump power dependent emission studies show that the material is suitable for optical sensing application. The intense green emitting phosphor is also useful in display device application.