Up-conversion luminescence of GdVO_4:Nd~(3+)/Er~(3+) and GdVO_4:Nd~(3+)/Ho~(3+) phosphors under 808 nm excitation

摘要

In recent years, there exists a tendency in research of up-conversion materials to shift excitation from 980 nm to shorter wavelengths. Here, in order to produce up-conversion luminescence emission of GdVO4-based materials under 808 nm excitation, polycrystalline powders of GdVO4:Er3+/Nd3+ and GdVO4:Ho3+/Nd3+ were successfully prepared by a high-temperature solid-state reaction technique. The prepared powders were highly crystalline with a single-phase zircon-type GdVO4 structure and consisted of micrometer-sized irregular spherical particles (2-6 mu m in diameter). In all studied samples, visible up-conversion luminescence was successfully achieved under 808 nm illumination. Near-infrared pumping produced emission bands in the green, yellow orange and green regions of the visible spectrum. The bands in the green and red regions of GdVO4: Er3+/Nd3+ as well as GdVO4:Ho3+/Nd3+ were, respectively, characteristic of Er3+ and Ho3+ ions. The dominant band originating from the (4)G(7/2) -> I-4(11/2) transition in Nd3+ ions was observed around 597 nm in all samples.