Effect of Tm³⁺ Concentration and Temperature on Blue and NIR Upconversion Luminescence in Tm³⁺/Yb³⁺ Co-Doped NaY(WO₄)₂ Microstructures

Abstract

Tm³⁺/Yb³⁺ codoped NaY(WO₄)₂ microstructures with various Tm³⁺ concentrations and 10 mol% Yb³⁺ concentration were prepared by a microwave-assisted hydrothermal method, and their upconversion luminescence (UCL) was investigated. Under excitation at 980 nm, Tm³⁺/Yb³⁺ codoped NaY(WO₄)₂ exhibited strong blue and near infrared (NIR) emissions, respectively, corresponding to ¹G₄ --> ³H₆ and ³H₄ --> ³H₆ transitions, with weak red emission due to the ¹G₄ --> ³H₄ transition. The optimum doping concentrations of Tm³⁺ for the highest blue and NIR UCL were investigated, and it was found that the optimal concentrations for blue and NIR emissions were 0.5 mol% and 1.5 mol%, respectively. In addition, an analysis of temperature dependent blue and NIR UCL in both the samples with low and high Tm³⁺ concentrations, respectively, was undertaken. The results implied that the sample with low Tm³⁺ concentration displayed more obvious effect on the thermal quenching of ¹G₄ level.

REVO4‐Based Nanomaterials (RE = Y, La, Gd, and Lu) as Hosts for Yb3+/Ho3+, Yb3+/Er3+, and Yb3+/Tm3+ Ions: Structural and Up‐Conversion Luminescence Studies

“…Rare‐earth vanadate matrices REVO 4 were co‐doped with the pairs of lanthanide ions: 20% Yb 3+ and 1% Ho 3+ , 20% Yb 3+ and 1% Er 3+ , and 20% Yb 3+ and 0.5% Tm 3+ . Concentrations were chosen on the basis of literature and are known to usually provide effective up‐conversion luminescence …”

“…Concentrations were chosen on the basis of literature and are known to usually provide effective up-conversion luminescence. [45][46][47] (2) Apparatus The physicochemical properties of the prepared compounds were studied with the use of X-ray diffraction analysis (XRD), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), and spectroscopic measurements: excitation and emission spectra, luminescence decays, dependence between the intensity of luminescence and energy of the laser as an excitation source.…”

Preparation of REE-doped NaY(WO4)2 single crystals for quantitative determination of rare earth elements in REE:NaY(WO4)2 laser crystals by LA-ICP-MS

“…Then, a problem arises as to what is the optimal concentration of REEs to be doped, which is interesting for researchers and many studies have focused on investigating the influence of the REE concentration on crystal optical properties like up-conversion efficiency. 8–11 It was found that the transmission and emission spectra, up-conversion efficiency and some other optical properties are dependent on the doped REE concentration. From this perspective, accurate determination of the REE concentration in NaLn(WO 4 ) 2 laser crystals is of vital importance for quality control of these crystals.…”

Nano-Crystallization of Ln-Fluoride Crystals in Glass-Ceramics via Inducing of Yb3+ for Efficient Near-Infrared Upconversion Luminescence of Tm3+

“…Thus, Yb 3+ -Tm 3+ co-doped materials were more efficient candidates for NIR-to-NIR UC luminescence and were significant light sources for biologically non-destructive detection. In the past decades, a large number of investigations about Yb 3+ -Tm 3+ co-doped UC materials have been widely reported for achieving high-efficiency NIR UC luminescence [14][15][16][17][18][19][20].…”