This study presents first the fabrication of a composite material based on Multi-Walled Carbon Nanotubes (MWNT/CNT) synthesised by an aerosol-assisted Catalytic Chemical Vapour Deposition (CCVD) process into continuous and verticaly aligned carpets, and on an epoxy polymer matrix. Then the characterisation of the material's structure and surface is described. And then, its electrical transport properties are studied. The electrical conduction at room temperature is measured. First, locally by a Current-Sensing AFM (CS-AFM) so that the CNTs are characterized at an individual scale. Then, at the macroscopic scale, so that the material's properties are characterized when its size is easy at use. This study shows that the resistivity is low and anisotropic. Significant fluctuations (approximatively by a factor 10) in the macroscopic resistance exist from one measurement to an other. The nature of these fluctuations is discussed. The electrical conduction at low temperature (from 4 to 50◦K) displays at a macroscopic scale the same mesoscopic electric transport properties than individual CNTs. In particular, a conductance scaling law in function of the temperature and the voltage ("Zero Bias Anomaly") has been observed, as well as a weaklocalization (WL) law. Moreover, the conductance distribution measured by CS-AFM allows to demonstrate this persistence's origin with a simple and realistic model.
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