Structural and optical properties of ZnWO4:er3+ crystals

Erbium ion- (er3+-) doped znwo4 crystals were synthesized via a hydrothermal method with different erbium concentrations. the prepared materials were characterized by x-ray diffraction (xrd),scanning electron microscopy (sem),and raman,uv-vis,and photoluminescence (pl) spectroscopy. for znwo4:er3+ crystals,a pure phase of znwo4 was obtained without any evidence of impurity present. the sem images show that the grain size and morphology of znwo4:er 3+ material depends on the er3+-dopant concentration. the uv-vis spectra of znwo4:er3+ compounds exhibited an absorption band at about 323 nm (3.83 ev) stemming from the [wo 4]2-. other absorption bands centered at 367,379,408,490,and 522 nm are related to er3+-ion transitions. room temperature pl spectra of the znwo4:er3+ compounds exhibited visible emission at 515-540 and 545-565 nm corresponding to the 2h 11/2-4i15/2 and 4s 3/2-4i15/2 transitions of er3+ ions,respectively. © 2013 nguyen van minh et al.