Color tunable up-conversion emission from ZrO2:Er3+,Yb3+ textile fibers†
Abstract
ZrO2:xEr3+,yYb3+ fibers (diameters of approximately 1 μm) with good flexibility and toughness were synthesized via electrospinning technology. The composition, morphology, and up-conversion photoluminescence properties of the fibers were investigated. The up-conversion photoluminescence mechanisms of ZrO2 fibers singly doped with Er3+ ions or co-doped with Er3+,Yb3+ ions are also discussed in detail, including decay curves, and lifetimes. The main mechanisms in ZrO2:xEr3+,yYb3+ fibers were energy transfer from Yb3+ to Er3+ and cross relaxation processes between Yb3+ and Er3+ or between adjacent Er3+ ions. When the concentration of Yb3+ was 4 mol%, emission intensity over the entire spectrum and lifetime of the 2H11/2/4S3/2 → 4I15/2 and 4F9/2 → 4I15/2 transitions in ZrO2:Er3+,Yb3+ fibers were maximized using 980 nm excitation light. When the concentration of Yb3+ was 20 mol%, pure red emission could be obtained. Different colors—green, yellow, and red—could be obtained with Er3+/Yb3+ concentrations. Given the chemical, thermal, and mechanical stability of zirconia, Er3+/Yb3+ co-doped ZrO2 up-conversion luminescence fibers may be an attractive choice for photonic materials.