Density functional theory study of rutile VO2 surfaces

Abstract

We present the results of a density functional theory (DFT) investigation of the surfaces of rutile-like vanadium dioxide, VO2(R). We calculate the surface energies of low Miller index planes, and find that the most stable surface orientation is the (110). The equilibrium morphology of a VO2(R) particle has an acicular shape, laterally confined by (110) planes and topped by (011) planes. The redox properties of the (110) surface are investigated by calculating the relative surface free energies of the non-stoichiometric compositions as a function of oxygen chemical potential. It is found that the VO2(110) surface is oxidized with respect to the stoichiometric composition, not only at ambient conditions but also at the more reducing conditions under which bulk VO2 is stable in comparison with bulk V2O5. The adsorbed oxygen forms surface vanadyl species much more favorably than surface peroxo species.

20 pages, 8 figures. To appear in the Journal of Chemical Physics

References in corpus (4)

• VO2: A Novel View from Band Theory
• Effective band-structure in the insulating phase versus strong dynamical correlations in metallic VO2
• Mind the gap but also the spin: why the Heyd-Scuseria-Ernzerhof hybrid functional description of VO2 phases is not correct
• Real space investigation of structural changes at the metal-insulator transition in VO2

Cited by in corpus (4)

• Evolutionary Method for Predicting Surface Reconstructions with Variable Stoichiometry
• Massively strained VO2 thin film growth on RuO2
• An oxygen-rich, tetrahedral surface phase on high-temperature rutile VO${}_2$(110)${}_{\text{T}}$ single crystals
• First principles studies of the electronic and structural properties of the rutile VO${}_2$(110) surface and its oxygen-rich terminations