The role of quantum-confined boron nitride nanotubes in gas monitoring: Adsorption and detection of NO, NO2, SO2, and SO3

This study investigates finite-length boron nitride nanotubes (4ZHBN-NTs) constructed from quantum dots for selective gas sensing, focusing on NO, NO2, SO2, and SO3. Adsorption energy calculations showed stable interactions, especially with SO3 (-2.805 eV). Natural bond orbital (NBO) analysis revealed significant charge transfer during adsorption, with NO2 and SO3 causing the highest electronic perturbations. Density of states (DOS) analysis confirmed strong gas-nanotube interactions through noticeable shifts in peak positions. Optical studies highlighted redshifts in absorption spectra, particularly for NO2, with wavelengths extending up to 418 nm. Recovery time analysis revealed fast desorption for NO and NO2, while SO3 exhibited prolonged retention due to its higher adsorption energy. These findings demonstrate the high sensitivity of 4ZHBN-NTs to gas adsorption, with distinct electronic and optical signatures for each gas, showcasing their potential as efficient sensors for environmental monitoring.