Abstract
We have performed studies on the correlation between mechanical deformation and conductivity on a set of-single wall carbon nanotubes (SW-CNT), in two. different forms: (a) tablets 0.5 mm thick obtained by compacting the nanotube material at 200 bar, and (b) membranes few tens of pm thick obtained by filtration.. The changes of conductivity have been monitored by measuring the current variations induced by a modulated periodic elongation via a coherent technique.
We have observed that there is a strong conductance modulation induced by the mechanical deformation of the CNT tablets, which is almost linearly proportional to the deformation and to the current bias. The CNT membranes are investigated considering a sample arrangement where the membrane is bonded to a Si tablet by mean of a Nafion(TM) adhesive layer. Both tablet and membranes present a conductance modulation at least one order of magnitude higher than what can be observed in reference,sample of graphite.
The gauge factor of piezoresistivity of SW-CNT membranes is measured, and is found to be ten times larger than in Silicon.