Thermometric properties of Na₂Y₂TeB₂O₁₀:Tb³⁺ green phosphor based on fluorescence/excitation intensity ratio

For noncontact optical thermometry, in contrast with fluorescence intensity ratio (FIR) technology, excitation intensity ratio (EIR) technology has been seriously limited due to low sensitivity. Moreover, by exploring all possible temperature-dependent response, developing multimode optical thermometry is of great importance. In this work, a new Na₂Y₂TeB₂O₁₀ (NYTB):Tb³⁺ phosphor is obtained by a solid-state reaction. Based on FIR and EIR models of Tb³⁺, thermometric properties are studied thoroughly. Excellent relative and absolute sensitivity (S_R and S_A) are acquired due to the significant difference in emission/excitation lines in response to temperature. Meanwhile, Tb³⁺ content-dependent luminescence quenching mechanism is discussed. This study shows a feasible route for exploiting well-performing FIR-/EIR-based thermometric materials.