Solution synthesis of Y1−xBixVO4 for optical applications (original) (raw)

Transparent luminescent Y 0.98-x Bi x Eu 0.02 VO 4 (0<x<1) ceramic films have been prepared using a polymeric route and heat-treatment at 550°C. A solid solution of zircon-type Y 1-x Bi x VO 4 is obtained for x values below 0.5 whereas phase separation is observed above this limit. The absorption spectra of the films show a shift of the band edge towards high wavelength with the bismuth content, as theoretical calculi have predicted. Luminescence of the films under a UV excitation is typical of europium ion in the zircon structure. The poor correlation between absorption and excitation spectra at high bismuth content is coherent with desexcitation in localized states of valence band. However, the excitation wavelength could still be tuned from deep-UV to near-UV range by inserting bismuth in YVO 4 .