Mechanism of carbon nanotube growth by Fe catalysts in a one-step process

Carbon nanotubes (CNT) have attracted much attention due to their wide range of applications, but the complex and time-consuming preparation of CNT by the traditional chemical vapor deposition (CVD) method has limited their large-scale production. In this study, we propose an innovative “one-step” CNT growth process to simplify catalyst preparation. The significant advantage of this method is that it reduces the time consumption by 90% compared with other catalyst preparation methods. Aluminum foil was found to outperform other materials as a substrate and catalyst loading significantly affected the morphology and quality of CNT. High-density, low-defect, high-crystallinity, and high-quality CNT could be grown on aluminum foil at the optimal loading (e.g., 0.10 mol/L.) In addition, the growth of CNT is affected synergistically by catalyst-substrate interfacial interactions, temperature, and aqueous solution content. In particular, CNT arrays with a diameter of 20 nm were successfully prepared on an iron catalyst calcined at 660 °C. These findings are important for large-scale, low-cost production of high-quality CNT.