Preparation of water-dispersible single-walled carbon nanotubes by freeze-smashing and application as a catalyst support for fuel cells

A simple freeze-smashing method is described to produce water-dispersible single-walled carbon nanotubes (SWCNTs). This is based on freezing SWCNTs in ice and then smashing it in a crusher. After the smashing process, SWCNTs are found to be dispersible in water without any addition of dispersant and destruction of the good graphitic structure. When such SWCNTs are used as a catalyst support for fuel cells, they show much better performance than the original SWCNTs, multi-walled carbon nanotubes and the commercial catalyst from Johnson Matthey Company as well. It is suggested that the present approach might be useful for preparation of water-dispersible single-walled carbon nanotubes in wide areas such as information technology, biomedicine, environmental and energy industries.