MWCNTs/SiO₂ Composite System: Carrier Transmission, Twin-Percolation and Dielectric Properties

We synthesize composite systems of multi-wall carbon nanotubes (MWCNTs)/SiO₂ by using the sol−gel method. The dielectric properties of the systems with different-concentration MWCNTs are studied. In our MWCNTs/SiO₂ inorganic systems, the twin−percolation phenomenon exists when the concentrations of MWCNTs are 5–10% and 15–20%. The permittivity and conductivity have jumping changes. The twin−percolation phenomenon is attributed to the special transfer mechanism of MWCNTs in the system, determined by hopping and migrating electrons. Variations of dielectric properties and conductance of the MWCNTs/SiO₂ systems are conformed to the percolation theory. The special percolation phenomenon and electric properties of MWCNTs/SiO₂ can help us comprehend the conductivity mechanism of the MWCNTs/SiO₂ systems effectively, and promote the development of a high performance function composite system.