Super-long continuous Ni nanowires encapsulated in carbon nanotubesElectronic supplementary information (ESI) available: SEM images. See http://www.rsc.org/suppdata/cc/b4/b405444j/

Super-long continuous Ni-filled carbon nanotubes were synthesized by the chemical vapor deposition (CVD) method with cloth-like single-walled carbon nanotube (SWNT) raw soot produced by the arc-discharge method as catalyst; the Ni nanowires inside the carbon nanotubes are single crystals, with an average diameter of 40 nm and up to tens of micrometres in length.