Symmetrical growth of carbon nanotube arrays on FeSiAl micro-flake for enhancement of lithium-ion battery capacity

The efficient and economic growth of high-purity carbon nanotube (CNT) arrays remains a great challenge due to the synthetic complexity and difficulty of high-precision control. Herein, a high-yield production method for direct symmetrical growth of CNT arrays using FeSiAl micro-flake catalyst was developed. The FeSiAl micro-flakes combined the role of the substrate, buffer layer, and catalyst, which led to ultra-high catalytic efficiency of 297% during catalytic chemical vapor deposition (CCVD). After carefully considering the reaction temperature and time, the growth kinetics and corresponding mechanism were investigated. As conductive additives, CNT arrays have excellent application potential in high energy density ternary cathode materials. The average specific discharge capacity was ∼160 mAh g−1 at 5 C, which represents a great improvement relative to commercially available conductive additive super p (SP). This FeSiAl micro-flake catalyst provides a novel methodology for the efficient and fast growth of CNT arrays on a large scale with potential applications in the energy storage and micro-nano device fields. [Display omitted] •FeSiAl micro-flakes directly promote the symmetrical growth of CNT arrays.•High-purity CNT arrays are obtained as high as ∼99.6% after purification.•The growth mechanism and kinetic process are confirmed.•The enhancement of battery specific capacity of CNT arrays is 143% of SP at 5 C.