Na5Rb7Sc2(WO4)9: Yb3+, Er3+: Luminescence Properties and Prospects for Non-Contact Thermometry

Abstract

Trigonal solid solutions Na5Rb7Sc1.95Yb0.05 – xErx(WO4)9 (x = 0.0025–0.0375) and Na5Rb7Sc2 – 5y-Yb2yEr3y(WO4)9 (y = 0.005–0.015) based on ternary tungstate Na5Rb7Sc2(WO4)9 have been obtained by ceramic technology and their luminescence properties have been studied. Excitation of powders by infrared radiation of the laser module (λex = 980 nm, Pmax = 45 mW/mm2) leads to the appearance of a bright green emission. The highest intensity of the bands at 515–540 nm (2H11/2 → 4I15/2), 540–575 nm (4S3/2 → 4I15/2), and 645–680 nm (4F9/2 → 4I15/2) is observed for sample Na5Rb7Sc1.95Yb0.02Er0.03(WO4)9. For a given composition, the power and temperature dependences of optical characteristics have been studied, a mechanism for energy transfer between optical centers has been proposed, and chromaticity coordinates have been determined. Based on the data obtained, it has been concluded that Na5Rb7Sc1.95Yb0.02Er0.03(WO4)9 can be used as a material for non-contact luminescent thermometry.