POST-TREATMENTS AND ADVANCED PROPERTIES OF CARBON NANOTUBE FIBERS FROM FLOATING CATALYST METHODS

Abstract

The fabrication of continuous carbon nanotube (CNT) fibers has paved the way to leverage the excellent mechanical and electrical properties of individual CNTs for practical macroscopic applications such as electronic devices and high-performance composites. However, weak inter-CNT interactions, impurities, and porous structures are crucial factors lowering the performance of the CNT fibers. This thesis aims to fabricate CNT fibers directly by floating catalyst method via a horizontal chemical vapor deposition reactor using methane and toluene as carbon sources. Additionally, the effects of different advanced post-treatment methods such as mechanical densification, acidization, epoxy infiltration, oxidative purification on fiber structures and properties were investigated comprehensively. Finally, the dissolution of CNT fibers in superacid, phase behavior of CNT solutions, and CNT length characterization were also investigated.