Materials
Typical inorganic nanotube materials are 2D layered solids such as tungsten(IV) sulfide (WS2), molybdenum disulfide (MoS2) and tin(IV) sulfide (SnS2). WS2 and SnS2/tin(II) sulfide (SnS) nanotubes have been synthesized in macroscopic amounts. However, traditional ceramics like titanium dioxide (TiO2) and zinc oxide (ZnO) also form inorganic nanotubes. More recent nanotube and nanowire materials are transition metal/chalcogen/halogenides (TMCH), described by the formula TM6CyHz, where TM is transition metal (molybdenum, tungsten, tantalum, niobium), C is chalcogen (sulfur, selenium, tellurium), H is halogen (iodine), and the composition is given by 8.2<(y+z)<10. TMCH tubes can have a subnanometer-diameter, lengths tunable from hundreds of nanometers to tens of microns and show excellent dispersiveness owing to extremely weak mechanical coupling between the tubes.
In 2007, Chinese scientists announced the creation in the laboratory of copper and bismuth nanotubes.
Read more about this topic: Inorganic Nanotube
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