Composite carbon nanotube/silica fibers with improved mechanical strengths and electrical conductivities

First synthesis of composite carbon nanotubes (CNT)/silica fibers with improved mechanical strengths and electrical conductivities, in which the CNTs are highly aligned, was reported. Pure CNT fibers were spun from high-quality CNT arrays, which were synthesized using the chemical-vapor-deposition (CVD) process. Building silicate molecules penetrate into smaller voids of CNT fibers to produce robust and strong silica networks after hydrolysis and condensation reactions. The conductivities of C2-derived composite fibers by direct casting and chemical modification are 121 S cm^-1 and 208 cm^-1 at room temperature. The results also show temperature dependence of the conductivity for both pure CNT fibers and composite CNT/silica fibers between 40 K and 310 K.