Multi‐Mode Optical Manometry Based on Li4SrCa(SiO4)2:Eu2+ Phosphors

• Published in: Advanced functional materials 2023-12, Vol.33 (49), p.n/a
• Main Authors: Su, Ke, Mei, Lefu, Guo, Qingfeng, Shuai, Pengfei, Wang, Yujia, Liu, Yukun, Jin, Yang, Peng, Zhijian, Zou, Bo, Liao, Libing
• Format: Article
• Language: English
• Subjects: Eu2+ luminescence; Europium; Materials science; Measurement methods; multi‐mode; optical manometers; Phosphors; Pressure measurement; Pressure sensors; pressure‐induced redshift; Red shift; Sensors; Structural stability
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.202305359

Optical manometry is a highly promising method for measuring pressure. However, its wider application is limited by the lower sensitivity and influenced by environmental factors. Herein, multi‐mode optical pressure sensors based on Eu2+‐doped Li4SrCa(SiO4)2 phosphors suitable for a variety of complex pressure‐measuring environments are designed. The phosphors contain two separate luminescence centers at 443 nm (EuSr) and 584 nm (EuCa), respectively. In the lower pressure range, the emission peak undergoes a massive redshift of 5.19 nm GPa−1 of EuCa, which is 14× better than commercially available ruby sensors. In order to improve the pressure response range and the accuracy of pressure measurement, for the first time, a new approach in the pressure readout method in which single Eu2+ ions doping based on fluorescence intensity ratio (FIR) pressure measurement is realized in designed materials. Meanwhile, the measured full width at half maximum (FWHM) as an indicator of pressure sensor performance also reveals that the sensing performance is d FWHM/d P ≈ 1.23 nm GPa−1 and d FWHM/d P ≈ 0.84 nm GPa−1 for EuSr and EuCa positions, respectively. Additionally, the structural stability of the phosphor is confirmed by in situ Raman spectrum. The above results indicate that the Li4SrCa(SiO4)2:0.04Eu2+ phosphor is a good candidate for multi‐mode optical pressure sensors. Pressure‐induced emission enhancement and tunable color of Eu2+‐doped Li4SrCa(SiO4)2 in the range of 1 atm–15.69 GPa are realized. A novel sample for multi‐mode optical pressure sensor proposes a multi‐mode pressure measurement method based on spectral redshift, fluorescence intensity ratio, and full width at half maximum. The pressure can be accurately read, which proves that the material that is designed has a strong, practical application value.