Investigation of up-conversion luminescent properties of Er3+/Yb3+ co-doped ZrO2–Al2O3 powders

Er3+/Yb3+ co-doped ZrO2–Al2O3 powders are prepared by a solid-state reaction method. The up-conversion luminescence spectra excited by 980 nm shows three main emission bands. One red emission band is centered at 654 nm and two green ones are centered at 545 and 525 nm, corresponding to the transitions of 4F9/2 → 4I15/2, 4S3/2 → 4I15/2 and 2H11/2 → 4I15/2 of Er3+ ions, respectively. The dependence of up-conversion luminescent properties on dopant concentrations is investigated. It is found that higher sintering temperature could make aluminum dissolved in the zirconia lattice in term of the XRD patterns. This enhances the up-conversion efficiency.