Geoinspired Synthetic Chrysotile Nanotubes

Since the discovery, in 1991, of hollow cylindrical carbon-based unidimensional structures, the nanotubular form of matter has been thoroughly investigated leading to a wealth of papers. Their particular features are not limited to graphite but are common in many inorganic highly anisotropic two-dimensional layered compounds. The first non-mineral inorganic nanotubes, constituted of lamellar molybdenum and tungsten disulfides, were synthesized in 1992. Afterwards, a large number of inorganic nanotubes has been synthesized, opening the path to the development of nanoelectronics, due to their dielectric properties. The unique mineral phase which crystallizes with a tubular morphology is chrysotile, that has been tentatively used to prepare ultra-thin wires by filling its hollow nanodimensional core with a conductive material. To overcome its natural heterogeneity in composition, morphology and structure, synthetic chrysotile-inspired nanotubes have been recently synthesized. These geoinspired nanotubes can be prepared with specific properties, finalized to focused achievements such as preparation of new quantum wires. The existing knowledge on the structural and physicochemical properties of mineral and synthetic chrysotile nanotubes is reviewed, with the aim of emphasizing their potential applications as non-linear optical and conducting technological devices. Bibliography encompasses over one hundred references.