Functionalized mesoporous and nanoporous materials

The organofunctionalization of porous material surfaces has been extensively investigated in the last two decades. Inherently porous material properties, such as geometrical selectivity and high surface area, combined with high activity and selectivity for many different physical and chemical processes, provided by different functional groups, allowing a wide range of powerful materials, resulted in diverse functionalities and variation in properties. These materials have been used for many applications in catalysis, sorption, drug delivery, energy technology and so on. The efficiency of these applications depends on many properties that are controlled by the synthetic pathways. The main preparation methods are discussed concerning the degree of functionalization and homogeneity as well as the inorganic structural organization achieved. The use of post-calcination functionalization demonstrates higher sorption capacity for many species and better activity in catalytic processes. However, in restricted cases of co-condensation, the organosilicas obtained present superior effectiveness for some uses, due to highly homogeneous distributions of pendant organic chains. The pore system organization level also determines the efficiency in most applications. Highlighted applications, mainly in the sorption and biomedical fields, are discussed to explain the contribution of the organic moiety incorporated on inorganic structures for each process, as well as the role of different properties, with emphasis in shape and size distributions.