Information for
Quick links
Faculties
The following text has been machine translated from the German with no human editing.
In medicine, engineering, construction and even sports, elasticity is a physical property that must be precisely tailored to the application and specific function of a material. 'It also plays a role in determining which underground rock formations are best suited for storing carbon dioxide. This is because porous materials change when their tiny cavities are filled with gaseous or liquid substances, causing their pore walls to deform,' explains physicist Dr. Klaus Schappert, who conducted the study together with Rolf Pelster, Professor of Experimental Physics at Saarland University.
Experimental and theoretical physicists have been investigating what influences the elasticity of nanostructures and how this affects the properties of materials for several years. Simulations and calculations by theoretical physicists in the USA had already suggested that porous materials can do more than just deform when liquids or gases penetrate them. They also alter their elastic behaviour when the respective substances penetrate the pores. 'In our experiment, we have now been able to demonstrate for the first time that the smaller the pores in the material, the more force is required to deform them,' says Klaus Schappert.
For their measurements, the Saarbrücken physicists used quartz glass with different pore radii on a tiny scale of 1.8 and 12.8 nanometres. To rule out interfering factors during the highly sensitive ultrasonic measurements, the material had to have as homogeneous a structure as possible. The researchers then filled the pores of the material samples with the liquid noble gas argon at minus 187 degrees Celsius. 'Although argon interacts only weakly with the pore wall, we were able to show that the elasticity of the filled material is twice as high in nanopores with a diameter of 12.8 nanometres as in the smaller pores with a radius of 1.8 nanometres,' says Klaus Schappert. Consequently, more force must be applied to deform the material in particularly tiny pore structures.
The Saarbrücken experimental physicists now intend to investigate further how material systems behave where there are even stronger interactions between solid and liquid or solid and gaseous substances. 'This is not only crucial for carbon dioxide storage, but is of importance wherever liquid or gaseous substances flow into the tiny cavities of a material and are to be stored there temporarily or permanently. This could also involve, for example, systems designed to absorb pollutants or filter out certain substances,' explains physicist Klaus Schappert.
Original publication:
Klaus Schappert and Rolf Pelster, Experimental Evidence for the Pore Size Dependence of Elastic Properties in a Liquid Adsorbate Confined to Nanopores, J. Phys. Chem. Lett. 17, 1640–1646 (2026), https://doi.org/10.1021/acs.jpclett.5c03903
Press photos for download, for royalty-free use in connection with this press release, can be found at the very bottom of the following webpage.
For further information, please contact:
Dr. Klaus Schappert
Chair of Experimental Physics and Physics Education
Tel.: +49-681-302-3032
Email: k.schappert(at)mx.uni-saarland.de
Prof. Dr. Rolf Pelster
Chair of Experimental Physics and Physics Education
Tel.: +49-681-302-2216
Email: rolf.pelster(at)mx.uni-saarland.de
