The Fascinating Story of Porous Materials

This paper briefly reviews the history of porous materials ab initio, i.e., starting from the discovery of hydrothermal zeolites in 1756 by Axel F. Cronstedt and, some two hundred years later, of the huge deposits of sedimentary zeolites. The major stages of the subsequent route are considered in some detail, particularly those leading to relevant changes in the conception of the synthesis environments and techniques. Attention is therefore paid to (a) the synthesis of aluminosilicate zeolites, (b) the introduction of organic templates with the consequent synthesis of silica-rich and silica zeolites, (c) the incorporation of heteroatoms in zeolite frameworks, (d) the overcoming of the traditional zeolite concept and the synthesis of the non-silica molecular sieves, (e) the enlargement of the field of microporous materials with the synthesis of mesostructures, and finally (f) the obtainment of inorganic-organic hybrids. Some information on the major properties of the most important materials and on their real or potential uses is also given.