Scalable manufacturing of carbon nanotubes on continuous carbon fibers surface from chemical vapor deposition

A novel process has been successfully developed to grow carbon nanotubes (CNTs) on continuously moving carbon fibers (CF) surface by a unique open-ended chemical vapor deposition (CVD) furnace. Systematic researches were carried out under various deposition temperatures, velocities of continuous carbon fibers and catalyst concentrations. The morphologies and structures of CNTs were investigated by field emission scanning electron microscopy (FESEM) and high resolution transmission electron microscopy (HRTEM), which indicated clearly that carbon fibers with uniformly distributed CNTs were achieved, with the optimum parameters of 650 °C deposition temperature and 6 cm min−1 velocity of continuous carbon fibers and 0.05 M catalyst concentration, respectively. By means of the single fiber push-out tests, the interfacial shear strength (IFSS) of carbon fibers growing CNTs was increased significantly by 84.4% compared to the desized carbon fibers. Furthermore, the results of single fiber tensile test verified that there is scarcely any degradation in the mechanical properties of carbon fibers after the growth of CNTs with the optimum parameters. This study provides a new and original vision for scalable manufacturing of CNTs on continuous moving substrate, when compared to the traditional batch process.