Strong luminescence intensity and high temperature sensitivity of Er3+-doped KYb(MoO4)2 phosphors optimized by codoping trivalent ions

Rare earth doped upconversion luminescent materials have the advantages of low toxicity, high chemical sta-bility, excellent photostability, narrow emission band, and long luminescent life, but their low fluorescence quantum efficiency restricts their practical application in the field of temperature sensing. In this paper, Er3+ doped KYb(MoO4)2 (KYM) phosphors were synthesized by a temperature solid state reaction method. When the doped concentration is 5 mol%, the luminescence intensity get its strongest value. On this basis, 2 mol% trivalent ions Gd3+, La3+ and Y3+ (R3+) were doped respectively, and the luminescence intensity increased by about 2 times. By the fluorescence intensity ratio technique, the KYM:5Er phosphor has the maximum absolute tem-perature sensitivity of 0.0106 K-1. By codoping 2 mol% Gd3+ in KYM:5Er, the upper limit of temperature measurement increased from 513 K to 663 K, which shows that Er3+-doped and Er3+/R3+-codoped KYM have the potential as temperature sensors.