A strategy towards macroporous sponge-like networks of metal oxide-surfactant mesophases and bulk metal oxides

A methodology to prepare macroporous sponge-like networks of either mesostructured metal oxides or bulk metal oxides is reported. It uses bubbling oxygen gas released from hydrogen peroxide decomposition, through clear metal oxide gels with or without surfactant assemblies as mesostructure directors. The resulting inorganic sponge-like materials of various compositions such as SiO2, TiO2 and Nb2O5 consist of curved walls, 0.5–1.0 µm in thickness, of mesostructured or bulk metal oxides. This approach could possibly be extended to a wide variety of inorganic materials and should have significant benefits as the method is simple, inexpensive and amenable to scale-up and processing.