Multiscale adsorption and transport in hierarchical porous materials

Abstract

This review presents the state-of-the-art of multiscale adsorption and transport in hierarchical porous materials, i.e. solids combining different porosity scales (from nm to > μm). Adsorption and desorption phenomena that can be observed in ordered and disordered porous materials are first discussed (including a discussion of the effect of pore size/confinement on the critical behavior of confined fluids). The general behavior of adsorption in hierarchical porous materials is then presented with a special emphasis on characterization techniques to probe the morphology (pore disorder) and topology (connectivity) of the pore network. As for transport, after a presentation of the different diffusion mechanisms that can be observed in porous solids depending on the pore scale, a brief discussion of the theoretical frameworks available to describe multiscale transport is provided. The results obtained for transport in hierarchical porous solids are then reviewed together with some upscaling strategies that can be used to build a bottom-up description of multiscale transport in hierarchical porous media.