Adsorption of polycyclic aromatic hydrocarbon (PAH): A computational study of naphthalene interactions with chemically functionalized nanotubes

Abstract

Petroleum hydrocarbon environmental pollution, particularly naphthalene (NTL), poses a grave threat to ecosystems and human well-being due to its toxicity and persistence. There is an urgent need for proper detection and removal, necessitating the development of highly selective adsorbent materials. In the present work, density functional theory (DFT) was applied to investigate the adsorption feasibility of newly structured Fe-Se@SiCNT, Os-Se@SiCNT, and Ru-Se@SiCNT nanomaterials at the DFT/MN12SX/LANL2DZ level of theory. The adsorption of naphthalene onto these functionalized nanotubes resulted in the creation of stable complexes titled NTL@Fe, NTL@Os, and NTL@Ru, with all structures exhibiting chemisorptive interactions. Among all the materials studied, Fe-Se@SiCNT was determined to possess the highest adsorption affinity, with an adsorption energy of −1.130 eV, indicating a strong interaction. Notably, the pre-adsorption electronic bandgaps of 1.042 eV (Fe-Se@SiCNT), 0.776 eV (Os-Se@SiCNT), and 0.743 eV (Ru-Se@SiCNT) widened significantly after adsorption, suggesting enhanced electrical conductivity. These findings offer a fundamental basis for the rational development of novel nanomaterials for hydrocarbon detection and environmental remediation, and potential applications in industrial safety and atmospheric pollution monitoring.