Elucidating NO x Surface Chemistry at the Anatase (101) Surface in TiO 2 Nanoparticles.

Understanding NO x chemistry at titania nanoparticle surfaces is important for photocatalytic environmental remediation processes. We focus on this problem and put forward an experimental-computational approach based on vibrational spectroscopy grounds. Temperature-dependent IR experiments of NO x adsorption on shape-engineered nanoparticle (101) anatase surfaces are paired with power spectra obtained from Born-Oppenheimer trajectories. Then, the harmonic versus anharmonic vibrational frequencies of several adsorption scenarios are directly compared with the IR experiments. We conclude that molecules are adsorbed mainly by the N-end side and both the intermolecular interactions between adsorbed molecules and (NO) 2 dimer formation are responsible for the main NO adsorption spectroscopic features. We also investigate the spectroscopy and the mechanism of formation on defective anatase surfaces of the long-lived greenhouse gas N 2 O.