Affiliation:
1. Department of Chemistry and Physics, Prairie View A&M University, Prairie View, TX 77446, USA
Abstract
Carbon nanotubes (CNTs) are often regarded as semi-rigid, all-carbon polymers. However, unlike conventional polymers that can form 3D networks such as hydrogels or elastomers through crosslinking in solution, CNTs have long been considered non-crosslinkable under mild conditions. This perception changed with our recent discovery of UV-defluorination-driven direct crosslinking of CNTs in solution. In this study, we further investigate the thermal stability of UV-defluorination-driven crosslinked CNTs, revealing that they are metastable and decompose more readily than either pristine or fluorinated CNTs under Raman laser irradiation. Using Raman spectroscopy under controlled laser power, we examined both single-walled and multi-walled fluorinated CNTs. The results demonstrate that UV-defluorinated CNTs exhibit reduced thermal stability compared to their pristine or untreated fluorinated counterparts. This instability is attributed to the strain on the intertube crosslinking bonds resulting from the curved carbon lattice of the linked CNTs. The metallic CNTs in the crosslinked CNT networks decompose and revert to their pristine state more readily than the semiconducting ones. The inherent instability of crosslinked CNTs leads to combustion at temperatures approximately 100 °C lower than those required for non-crosslinked fluorinated CNTs. This property positions crosslinked CNTs as promising candidates for applications where mechanically robust, lightweight materials are needed, along with feasible post-use removal options.
Funder
USDA National Institute of Food and Agriculture (USDA-NIFA)’s1890 Land Grant Institution Capacity Building Grants (CBG) Program
Reference65 articles.
1. Magical allotropes of carbon: Prospects and applications;Tiwari;Crit. Rev. Solid State Mater. Sci.,2016
2. Carbon nanotubes: Present and future commercial applications;Tawfick;Science,2013
3. The rise of graphene;Geim;Nat. Mater.,2007
4. Hole-punching for enhancing electrocatalytic activities of 2D graphene electrodes: Less is more;Gao;J. Chem. Phys.,2020
5. Review on grain boundaries in graphene. Curved poly- and nanocrystalline graphene structures as new carbon allotropes;Rev. Adv. Mater. Sci.,2012