TiO2/Graphene oxide nanocomposite as an ideal NO gas sensor: A density functional theory study

We performed a density functional theory investigation on the structural and electronic properties of pristine and nitrogen-doped TiO2/Graphene oxide nanocomposites as the adsorbents for the removal of toxic NO molecules in the environment. We presented the most stable adsorption configurations and examined the interaction of NO molecule with these doped and undoped nanocomposites. It turns out that the NO molecule is preferentially adsorbed on the active oxygen and nitrogen atom sites of nanocomposite. The insights of the computations include the structural and electronic analyses such as bond lengths/ angles, adsorption energies, density of states (DOSs) and molecular orbitals. It was found that the adsorption of NO on the N-doped nanocomposite is energetically more favorable than the adsorption on the undoped one, representing the higher reactivity of N-doped nanocomposites with NO molecule. It means that the adsorption on the N-doped nanocomposite provides the most stable configurations and consequently the most efficient adsorption processes. Nevertheless, our computational study on TiO2/Graphene oxide nanocomposites suggests that the N-doped nanocomposites are more sensitive than the undoped ones when utilized as detectors or sensors for NO detection.