Abstracts

Pressure is a fundamental physical parameter in the description of nature. Precise determination of pressure value remains a challenging process, especially for non-standard systems or under extreme pressure conditions. Inorganic materials doped with optically active ions (such as lanthanides or transition metals) represent some of the most promising materials for accurate pressure value determination without direct contact. Their physical stability allows for their utilization in various pressure conditions, ranging from partial vacuum to high-pressure conditions in the GPa range. Luminescence properties investigations under high-pressure conditions are carried out using the Diamond Anvil Cell (DAC), with the ruby R1-line shift serving as a conventional high-pressure indicator. Investigations at low pressure (partial vacuum) are possible in vacuum chambers equipped with vacuum pumps and standard manometers. Investigation of novel, advanced optical pressure sensors enables contactless monitoring of the pressure variations in extreme conditions.The internal crystal structure of materials undergoes changes (plastic or elastic deformation) under high-pressure conditions. The unit cell volume and inter-ionic distances decrease, leading to alterations in the local surroundings of optically active ions and resulting in changes in their excited energy levels. Such degenerations manifest as observed changes in photoluminescence properties, e.g., blue/red emission band shift, variations in band intensity ratio, changes in the luminescence color, modifications of the bandwidth, or alteration in luminescence lifetime under varying pressure conditions [1]. On the other hand, in low pressure (partial vacuum), the intensified laser-induced heating of materials (light-to-heat conversion) occurs, resulting from impeded convection caused by a reduction in the number of air molecules and boosted thermalization of excited states [2]. Here, we present the different strategies and current results in contactless pressure sensing with the use of luminescence properties of inorganic materials doped with f- or d-block ions. The utilization of novel, optical manometers can be determined and compared with other potential luminescent manometers by calculation of the two main manometric parameters i.e., absolute sensitivity (S_a) and relative sensitivity (S_r) [3]. The development of luminescent pressure sensors, i.e., optical, contactless manometers, offers new possibilities for monitoring changes in the spectroscopic properties of materials under extreme pressure conditions (from vacuum to high-pressure), thereby enabling remote determination of pressure value in the investigated systems. This research opens up new possibilities in advanced technologies for nano-scale and extraterrestrial research.References:[1] P. Woźny, et. al., J. Lumin., 2019, 209, 321-327.[2] M. Runowski, et. al., J. Mater. Chem. C, 2021, 9, 4643-4651.[3] Ł. Marciniak, et. al., Coord. Chem. Rev., 2024, 507, 215770.