High sensitivity and multicolor tunable optical thermometry in Bi3+/Eu3+co-doped Ca2Sb2O7 phosphors

Currently, with increasing demand for non-contact fluorescence intensity ratio-based optical ther-mometry, a novel phosphor with high-efficiency, dual-emitting centers, and differentiable temperature sensitivity is more and more urgent to develop. In this work, an efficient dual-emitting center optical thermometry with high sensitivity and multicolor tunable in Ca2Sb2O7:Bi3+, Eu3+ phosphor is firstly designed and successfully prepared. Under 330 nm excitation, the fabricated phosphor presents the featured and distinguishable emissions of Bi3+ and Eu3+ ions. The high efficiency energy transfer from Bi3+ to Eu3+ ions is proved and its corresponding mechanism belongs to dipole-dipole interaction. By modulating the ratio of Bi3+/Eu3+, the multicolor changes from blue to pink are realized. Based on the discriminative thermal quenching behavior between Bi3+ and Eu3+, the fluorescence intensity ratio of Eu3+ to Bi3+ in Ca2Sb2O7 samples illustrates excellent optical thermometry performance from 298 to 523 K. The maximum absolute sensitivity (Sa) and relative sensitivity (Sr) reach as high as 0.2773 K-1 at 523 K and 2.37% K-1 at 448 K, respectively. Notably, the discriminated surrounding temperature can be directly confirmed by observing the emitting color from purple to orange-red with the temperature increase from 298 to 523 K. Furthermore, the as-prepared phosphor materials also demonstrate outstanding repeatability and excellent reversibility. These results exhibit that the designed Ca2Sb2O7:Bi3+, Eu3+ phosphors have great promising applications in the field of non-contact optical temperature thermometry and thermochromic.(c) 2022 Elsevier Ltd. All rights reserved.

Automated summary

In this work, an efficient dual-emitting center optical thermometry based on Ca2Sb2O7:Bi3+, Eu3+ phosphor is designed and prepared. By modulating the ratio of Bi3+/Eu3+, the multicolor changes from blue to pink are realized. The fluorescence intensity ratio of Eu3+ to Bi3+ in Ca2Sb2O7 samples demonstrates excellent optical thermometry performance, with maximum absolute sensitivity (Sa) and relative sensitivity (Sr) reaching as high as 0.2773 K-1 and 2.37% K-1, respectively. The as-prepared phosphor materials also exhibit outstanding repeatability and reversibility, showing great potential in the field of non-contact optical temperature thermometry and thermochromic.