Characterization of Hierarchically Ordered Porous Materials by Physisorption and Mercury Porosimetry—A Tutorial Review

This paper is devoted to the textural characterization of nanoporous materials with a focus on hierarchically ordered materials such as mesoporous zeolites, which exhibit an interconnected pore network consisting of micro‐, meso‐, and often macropores. Hierarchically ordered zeolites have the potential to improve various industrial applications for instance in the areas of heterogeneous catalysis, separation, gas, and energy storage. Detailed insights into the pore architecture are important, because they control transport phenomena, diffusional rates, and govern selectivity, e.g. in catalyzed reactions. However, a reliable characterization of such complex pore structures is still a major challenge. Within this context, the application of advanced physisorption methodologies for micro‐mesopore analysis is discussed but also the characterization of macroporosity by mercury porosimetry is addressed. Fundamental concepts and recent major advances in understanding the underlying mechanisms are highlighted. In conjunction with selected case studies, it is illustrated how the application of advanced physisorption methodologies allows i) for the determination of reliable surface areas, pore volumes, and pore size distributions and ii) for obtaining information about pore network characteristics. This tutorial offers guidance for an advanced characterization of nanoporous materials by physisorption and mercury intrusion/extrusion. This tutorial highlights important concepts and offers practical guidance for the advanced characterization of nanoporous materials using gas adsorption in combination with mercury porosimetry, mainly focusing on hierarchically ordered materials. In conjunction with selected case studies, the application of advanced methodologies to obtain reliable surface areas, pore volumes, pore size distributions, and information about pore network characteristics is discussed.