A Potential High-Throughput Route to Collagen-Mimicked Carbon Nanotube Fiber via Domino Pushing and Ion Bombardment

Carbon nanotubes (CNTs) have been shown owning extraordinary mechanical properties for decades, but to date, their wide application as load-bearing structural materials has not been realized mainly due to the critical obstacles of weak interface, poor distribution and alignment, and lack of economic technology for mass production and processing. In order to overcome these obstacles, we proposed a potential route from as-grown CNT forest to collagen-mimicked CNT films with covalently crosslinked CNTs arranged in a staggered alignment. To consolidate the foundation of the route, its critical step of ion bombardment to construct the intertube crosslinks in CNT films was simulated using molecular dynamics simulations. Results show that the ion bombardment can efficiently construct the intertube crosslinks and greatly improve the elastic modulus and strength of CNT films by as much as 24% and 660%, respectively, with comparison to the nonbombarded ones. The influences of the number and the kinetic energy of the incident particles were systematically investigated and the corresponding contours were presented, suggesting the optimal energy and number of the incident particles for the elastic modulus and strength of collagen-mimicked CNT films. The work not only provides a novel route to mass fabrication of high-performance CNT fibers but also gives useful guidelines on the optimization of processing design.