Emission in Gd6O5F8:Yb3+,Er3+ micro-particles for multimodal luminescence and temperature sensing upon 980 nm excitation

Abstract

Mono-dispersed Gd₆O₅F₈:Yb³⁺/Er³⁺ micro-particles with different doping concentrations (Er³⁺: 0.1–1%) were synthesized by a facile hydrothermal route. The emission spectra, luminescent dynamic power-dependence and temperature sensing of up-conversion photoluminescence were investigated in detail. Under 980 nm excitation, the as-prepared samples exhibit intense red up-conversion and NIR emissions, which are influenced by the doping concentrations of Er³⁺ within Gd₆O₅F₈. With increasing concentrations of Er³⁺ ions, the visible up-conversion emissions first increase and then decrease, but NIR down-conversion emissions display a distinct trend, in which one peak at 1010 nm is highly suppressed and another at 1530 nm is increased quickly. Furthermore, the 980 nm excited optical temperature sensing property of the synthesized sample is realized over a wide temperature range by monitoring the intensity of up-conversion luminescence. The study provides a novel strategy based on lanthanide oxy-fluoride micro-particles for multifunctional displays, lighting and temperature sensing in a single system.