Highly Sensitive Lifetime-Based Luminescent Manometer on Mn⁴⁺ Luminescence in Sr₄Al₁₄O₂₅ Mn⁴⁺

Enabling remote and temperature-independent pressure sensing based on luminescence kinetics holds significant potential for the development of a luminescence pressure sensor with a wide array of applications. To meet these requirements, in this work, a unique lifetime-based luminescence manometer is demonstrated for which an increase in pressure results in an elongation of lifetime of E-2 state of Mn4+ due to a change in the probability of radiative depopulation of the E-2 level of Mn4+ ions with an unprecedentedly high sensitivity of 35% GPa(-1). Furthermore, the pressure-induced modification in the covalency of the Mn4+O2- bond facilitates a manometer operating in spectral band shift and ratiometric modes with sensitivities of 26 cm(-1) GPa(-1) (1.2 nm GPa-1) and 24.8% GPa(-1), respectively. This study firmly supports the belief that the distinct pressure-dependent kinetics governing the depopulation of Mn4+ ions at the E-2 level, along with the resulting advantageous manometric performance, will pave the way for a new research trajectory in luminescence manometry.