Nondestructive high-throughput screening of nanopore geometry in porous membranes by imbibition: Laser-Interferometry and Dilatometry Experiments

Z. LI; FLOUDAS, GEORGE; RAÚL URTEAGA; CENCHA, LUISA G.; BERLI, CLAUDIO L. A.; HUBER, PATRICK; CALZADO J.S.; KAPPL, MICHAEL; STEINHART, MARTIN

Congreso; InterPore2020; 2020

Indico

Nanoporous media, in particular, monolithic porous membranes play an increasing scientifc andtechnological role. Among the applications of porous membranes stand out fltration and separationprocesses, the study of confnement effects in sof mater, and energy harvesting. However, theircharacterization in terms of pore size and pore homogeneity is still an extremely demanding experimental task, even though it is of crucial importance for the interpretation of experiments and for the understanding of functional performance of nanoporous membranes. The sample requirements for the most prominent characterization methods of nanoporous materials, such as volumetric sorption isotherm measurements, mercury porosimetry, and electron microscopy, necessitate powders for small sample pieces and thus a destruction of the porous medium. Here, we present a theoretical analysis showing that simple, capillarity-driven flling experiments allow one to nondestructively analyze the pore geometry of macroscopic porous membranes with nanoscale spatial resolution in terms of pore diameter (gradients) 1. Moreover, we validate this method by experiments on the imbibition dynamics of several selected simple liquids in archetypical monolithic nanoporous media, i.e., anodic aluminum oxide (AAO) membranes. Additionally, we present dilatometry experiments on imbibition-induced deformation dynamics for water in nanoporous carbon, silica and polymers. These experiments document a competition of surface-stress and Laplace pressure contributions during the imbibition process [2,3,4] that also allows us to infer information on the pore size of monolithic nanoporous solids.1 Nondestructive high-throughput screening of nanopore geometry in porous membranes by imbibition.Luisa G. Cencha, Patrick Huber, Michael Kappl, George Floudas, Martin Steinhart, Claudio L. A. Berli,and Raul Urteaga Applied Physics Leters 115, 113701 (2019).2 Elastic response of mesoporous silicon to capillary pressures in the pores. Gennady Gor, Luca Bertineti,Noam Bernstein, Peter Fratzl and Patrick Huber. Applied Physics Leters 106, 261901 (2015).[3] Adsorption-induced deformation of nanoporous materials - A review. Gennady Gor, Patrick Huberand Noam Bernstein. Applied Physics Reviews 4, 011303 (2017).[4] Elastocapillarity in nanopores: Sorption strain from the actions of surface tension and surfacestress. Gennady Y. Gor, Patrick Huber and Jörg Weissmüller. Physical Review Materials 2, 086002(2018).