Hierarchical porosity components by infiltration of a ceramic foam

A ceramic body with hierarchical meso–macro-porosity was prepared by depositing a mesoporous silica coating on the walls of a macroporous silicon oxycarbide (SiOC) foam. Scanning electron microscopy, transmission electron microscopy, and small-angle X-ray scattering revealed that a uniform mesoporous coating was deposited on the walls of the macropores, with the mesopores arranged in a highly ordered cubic lattice. Nitrogen adsorption measurements showed a bimodal pore size distribution and revealed that the specific surface area is one order of magnitude higher than in macroporous SiOC foams. Therefore, interesting applications in adsorption and catalysis can be devised.