Exploiting the effect of twisting on the electrical resistance of a single-walled carbon nanotube rope to trigger ignition using a 9-V battery

The effect of twisting on the electrical resistance of a raw single-walled carbon nanotube (SWCNT) rope was investigated and found to increase with increasing number of twists, varying from 28.7 Ω initially to 35.2 Ω after 12 twists. There are two reasons for this. One is that the twisting generated more contact points between the SWCNTs and catalytic nanoparticles, resulting in a high density of high local resistance points. The other is that the protrusion of SWCNTs in a rope twisted a large number of times (12–15 twists) partially interrupted the conducting path. By using a 9-V battery, ignition of the rope could be produced at a threshold resistance between 17.5 and 21.1 Ω, and this could be used to ignite ferrocene with the process lasting for several minutes.