Leveraging the dimensionality effect of fluorinated carbon nanotubes to promote aluminum combustion

This work demonstrates that one-dimensional (1D) fluorinated carbon nanotubes (FCNTs) exhibit superior efficacy as a fluorocarbon additive for enhancing aluminum (Al) combustion, outperforming conventional 3D polytetrafluoroethylene (PTFE) and 2D graphene fluoride (GF). Through a combined approach of experimental diagnostics and reactive molecular dynamics (RMD) simulations, this work systematically evaluated the effects of three fluorocarbons on the energetic performance of Al. The unique 1D nanostructure of FCNTs leverages distinct advantages in regulating the combustion process via promoting intimate interfacial contact in the Al/FCNTs composite. Thermal behavior results show that FCNTs exhibit a higher onset decomposition temperature than GF and PTFE, demonstrating enhanced thermal stability. The Al/FCNTs composite can efficiently suppress pre-ignition coalescence and exhibited the shortest ignition delay time among all formulations. RMD simulations revealed that FCNTs facilitate Al fluorination, thus achieving the rapidest and greatest energy release. A clear correlation between the dimensionality of fluorocarbon and its efficacy in promoting ignition and energy release is established, following the trend: FCNTs (1D) > GF (2D) > PTFE (3D). Analysis of the condensed combustion products (CCPs) showed that the agglomeration-inhibition effect decreases in the order GF > FCNTs > PTFE. These findings highlight the significant potential of low-dimensional fluorocarbons, with 1D FCNTs offering a distinct advantage for next-generation Al-based energetic composites.