Mechanism of Reaction of H₂ on the (011) In₂O₃ Surface with a Preadsorbed Oxygen Molecule

Using the climbing image nudged elastic band (CI-NEB) method, we have calculated activation energies of reaction of H₂ with an oxygen molecule preadsorbed on the (011) In₂O₃ surface, resulting in the formation of a water molecule or hydroxyl group. In the latter process, one hydroxyl results from bonding of OH to a surface metal atom, and another, from bonding of hydrogen to lattice oxygen. Calculations show that the activation energies of these reactions differ little, 0.99 and 0.98 eV, respectively, but the thermodynamically favorable process is hydroxylation of the surface.