Super‐Sensitive Multi‐Modal Optical Manometer Based on Huge Pressure‐Induced Spectral Red‐Shift and Broadening of Mn<sup>2+</sup> Emission Band in Green‐Emitting Zn<sub>2</sub>GeO<sub>4</sub> Phosphors
Junpeng Xue, Marcin Runowski, Kevin Soler‐Carracedo, Przemysław Woźny, Alfonso Muñoz, Laihui Luo, Kun Chen, Yanping Huang, V. Lavı́n, Peng Du
Abstract
Abstract To overcome the small sensitivities of luminescent manometers, Mn 2+ ‐activated Zn 2 GeO 4 green‐emitting phosphors with admirable manometric characteristics are synthesized. The structural stability of the studied samples is theoretically and experimentally investigated. Moreover, as pressure elevates, a huge spectral red‐shift and a broadening of the emission band are observed in studied samples, contributing to color‐tunable luminescence, i.e., from green to yellow, and ultimately to orange–red. Specifically, when pressure increases to 6.76 GPa, the emission band centroid shifts from 535.9 to 634.9 nm, leading to a superior sensitivity of d λ /d p = 21.3 nm/GPa. Whereas, in the same operating pressure range, the full width at half maximum (FWHM) of the emission band rises from 32.3 to 102.9 nm, resulting in unprecedentedly high sensitivity of d FWHM /d p = 17.0 nm/GPa. Furthermore, through analyzing the pressure‐dependent color coordinates, a maximum sensitivity of 29.43% GPa −1 is achieved, when x ‐coordinate is adopted. Additionally, the applicability of the developed manometer is confirmed by a simple uniaxial pressure experiments to showcase its practical use in industrial and daily‐life purposes. Notably, the designed sensor exhibits the highest pressure sensitivities reported to date in different modes, namely, emission band centroid, FWHM and color coordinate, making supersensitive multimodal optical manometry a reality.