Multifunctional porosity in biochar

Biochar is the black fine-grained residue obtained by pyrolitic decomposition processes of biomass, achieved at moderate temperatures under oxygen-limiting conditions. This pyrolysis residue has a hierarchical pore structure resulting in a large specific surface area accompanied by a strong adsorption capacity. Due to the relevant presence of mesopores, biochar can have different roles in storage applications, ranging from for the adsorption of pollutant gases, such as carbon dioxide, to the shape-stabilization of phase-change materials (PCMs), used for thermal energy storage. Biochar is overcoming the leakage problem of PCMs by their encapsulation in the mesopores, whereas the same mesopores are the passageway to the micropores which constitute the packing space for gas adsorption.