Cyclo[16]Carbon for Sensing and Safe Handling of TNT and TATB: A DFT Investigation

Abstract

The development of advanced materials for the detection and safe handling of energetic compounds such as TATB (1,3,5-triamino-2,4,6-trinitrobenzene) and TNT (2,4,6-trinitrotoluene) is critical for defense, homeland security, and industrial safety. However, current technologies often suffer from limited cost-efficiency, sensitivity, and real-world applicability. While traditional carbon allotropes such as graphene, fullerenes, and carbon nanotubes have been explored for explosive sensing and hazard mitigation, emerging sp-hybridized carbon nanostructures like cyclo[n]carbons remain underexplored. In this article, we present a theoretical investigation of cyclo[16]carbon (C₁₆), a novel sp-hybridized carbon ring, for interaction with energetic molecules. TNT was selected as a benchmark explosive due to its widespread use, whereas TATB was chosen for its remarkable insensitivity, allowing us to explore safe handling and adsorption scenarios. Our results reveal the formation of stable hollow-layered and sandwich-type supramolecular complexes with TNT and TATB via non-covalent C…O, C…N, and C…C interactions. Notably, the C₁₆–TNT and C₁₆–TATB complexes exhibit enhanced thermodynamic stability and reduced electrostatic sensitivity. Binding energy and electronic structure analyses indicate tunable optical properties, supporting the role of C₁₆ as a metal-free, spectroscopically active sensor. These findings underscore the dual functionality of cyclo[16]carbon in promoting safe handling and detection of high-energy materials, positioning it as a promising platform for passive sensing and hazard mitigation in challenging environments.