Luminescence properties of Ce3+–Dy3+ codoped aluminium oxide films

Photoluminescence properties of CeCl3 and DyCl3 codoped aluminium oxide films deposited by the ultrasonic spray pyrolysis technique were characterized by excitation, emission and decay time spectroscopy. When excited by ultraviolet radiation the films emit a combination of blue and yellow wavelengths through an efficient energy transfer from Ce3+ to Dy3+ ions (up to around 77%). From spectroscopic data it is inferred that such energy transfer is nonradiative in nature taking place between Ce3+ and Dy3+ clusters through a short-range interaction mechanism. In the Ce3+ doped single film the chromaticity coordinates are in the purplish blue region, whereas that in the cerium and dysprosium codoped films the coordinates move toward the white light emission region.

► A blue-yellow emission phosphor excited at UV can be manufactured with CeCl3 and DyCl3 codoped Al2O3 films deposited by spray pyrolysis. ►The addition of DyCl3 in the Al2O3:CeCl3 film leads to an efficient energy transfer from Ce3+ to Dy3+ under 290 nm excitation. ►The codoped film emission moves toward the white region from the purplish blue region of the Al2O3:CeCl3 film.