Carbon Nanotube Fillings

21 June 2007

Liquid or molten solids fill a porous structure of carbon nanotubes that act as capillary by capillary effects. Researchers first examined the inner structure of carbon nanotubes through computer simulation and later Ajayan and Iijima reported it that molten lead can be trapped inside the channels of Multi wall nanotubes (MWNTs). Thereafter various researchers carried out further encapsulation of various metal compounds in single wall nanotubes (SWNTs) and later the discovery of peapods open up new-diamensions.

Before capillary filling, the surface of carbon nanotube is wetted by foreign liquid having low surface tension. High surface tension material then can be filled in the carbon nanotube by chemical filling routes. Generally two methods wet chemistry solution method and molten method for chemical fillings is adopted. Filling in carbon nanotube is one of the effective tool for building nanodevices, nanorods, nanowires, nanocomposites etc.

Many researchers also carried out chemical reactions inside the capillary so that specific properties of the nanomaterial are modified. The capillary filling of the carbon nanotube is diameter dependant and both the chemical filling route have a common drawback of low filling effectiveness. Luzzi and his team in 1998 reported the existence of peapod chains. These peapods are formed by encapsulation of fullerene in single wall carbon nanotubes (SWNT).

Researchers found that peapods deform in the presence of electron beam irradiation in electron microscope. Encapsulation of fullerene in single wall carbon nanotubes modifies the local electronic structure of both carbon nanotube and fullerene. This capillary acts as a hybrid material having extraordinary properties.

Related Posts: