Adsorption, excitation analysis, and sensor properties of heteroatoms (S, P, Si) encapsulated gallium nitride nanotube for hexanol application: A computational approach

This study focuses on tunning the electronic behavior of heteroatoms (S, Si, P) doped gallium nitride nanotube (GaNNT) as a sensor material for detection and adsorption of hexanol (HXN) using density functional theory (DFT) at the B3LYP-gd3bj/def2svp level of theory. The calculated adsorption energies (−0.757, −0.956, and −0.603 eV for HXN_S@GaNNT, HXN_P@GaNNT, and HXN_Si@GaNNT, respectively) demonstrate a strong binding between the adsorbate and the surface, with phosphorus-doped GaNNT exhibiting the strongest adsorption. Non-covalent interactions, particularly π-π stacking, were observed in the HXN_S@GaNNT and HXN_P@GaNNT complexes, while the interaction of HXN with Si@GaNNT demonstrated strong interactions. Furthermore, the investigation of Hole-electron, Optical gap, and Exciton energy revealed a decreasing trend in exciton energy (HXN_Si@GaNNT > HXN_P@GaNNT > HXN_S@GaNNT) associated with weaker electron-hole interactions. HXN_P@GaNNT exhibited heightened electron-accepting potency, suggesting better sensor performance. The fraction of electron transfer (FET) values (0.355, 0.657, and 0.493 eV for HXN_S@GaNNT, HXN_P@GaNNT, and HXN_Si@GaNNT, respectively) indicated that HXN_P@GaNNT had superior sensor potential due to a higher FET value. This material holds promise for highly sensitive sensor applications, particularly in detecting trace amounts of specific gases or monitoring subtle environmental changes.