The effect of Y3+ co-doping on the persistent up-conversion luminescence of the ZrO2:Yb3+,Er3+ nanomaterials

The effect of the defects due to the charge compensation obtained with the yttrium co-doping to the ZrO2:Yb3+,Er3+ up-converting phosphors was studied. The materials were prepared with the combustion method. The materials purity was analyzed with the FT-IR spectroscopy. The crystal structure was studied with the X-ray powder diffraction and the crystallite sizes were estimated with the Scherrer formula. Up-conversion luminescence was excited at room temperature with an IR-laser at 970 nm. The up-conversion luminescence spectra showed red (650-685 nm) and green emission (520-560 nm) due to the 4F9/2→4I15/2 and (2H11/2,4S3/2)→4I15/2 transitions of Er3+, respectively. Persistent up-conversion luminescence was observed both in the Yb3+,Er3+ and Y3+,Yb3+,Er3+ doped materials.