Metal fluoride materials with complex pore structure and organic functionality

Abstract

For the first time, sol–gel derived metal fluorides (MgF₂, AlF₃ and CaF₂) were used in the preparation of three-dimensionally ordered macroporous solids with complex pore structures (macro-, meso- and micropores). These metal fluorides exhibit surface areas larger than 300 m² g⁻¹ and show medium to strong Lewis acidity which makes them attractive for catalytic applications and for gas adsorption and separation. It was shown that these properties are retained and complemented by the introduction of macropores. Here the preparation of films and bulk materials made from nano-metal fluorides with defined complex pore structure is reported. Furthermore, the use of organically modified magnesium fluoride sols has been explored for the case of phenyl phosphonic acid, allowing alteration of surface properties.