Natural nanosystems and synthetic mesoporous materials

One way to develop new advanced materials is to learn from the structures developed by living organisms. In the present work we show the synthesis of mesoporous silica that mimics many of the mollusc shell structures. We present the different external morphologies that can be produced. TEM examination shows that those structures are formed by nanopores with a approximately 4.4.nm spacing. The porous silica organizes itself into a mesostructure with different shapes. We also examine the microscopic structure of two natural materials; the radiolarian and the tectus pyramids shell. In the first case a structure composed by an hexagonal array of micropores can be observed. In the case of the tectus pyramids shell, it is formed by crystalline materials (calcite and aragonite) which self-organize at different levels. It is shown for the first time the transition layer between the two crystal structures. We also discuss the array of aragonite plates and the mechanism in which the external gyroid shape of the structure is formed.