Design and functionalization of halogenated hBN nanotubes for selective detection of halogenated volatile organic compounds: a DFT study

We investigate the selective detection of halogenated volatile organic compounds (VOCs) using hBN nanotubes through DFT calculations. Binding energy and vibrational frequency calculations, confirm the structural and dynamical stability of the nanotubes before and after halogenation. Pristine nanotubes have a 6.12 eV bandgap, reduced to 0.65 eV upon F-functionalization, as revealed by the partial density of states. The nanotubes demonstrate promising potential as VOC sensors, namely for C₆H₅Br, CCl₄, and CHF₃, with moderate adsorption energies enhanced by functionalization. Adsorption is predominantly physical, driven by van der Waals interactions, ensuring structural integrity. Cl-functionalized nanotubes exhibit faster recovery times, offering superior reusability compared to pristine and other halogenated variants. UV–vis spectra analysis reveals notable optical shifts upon VOC adsorption. These findings underscore the potential of halogenated hBN nanotubes as efficient, reusable, and optically responsive sensors for halogenated VOCs.