A method was presented for calculating the hydrogen effect upon the stability of oxygen vacancies in ZrO2 oxide in water. That method combines conventional electrodic and thermodynamic descriptions of electrochemistry with detailed first-principles calculations to take into account the ionic character of water. This allows identifying microscopic mechanisms that occur around the corrosion potential. At pH = 7 (the most often experimental conditions), it was found that VO–nH complex defects, where n was the number of hydrogen atoms trapped in an oxygen vacancy, were particularly stable emphasizing the major role that hydrogen could play in the oxidation kinetics of zirconium alloys observed in water.

Role of Water on the Stability of Oxygen Vacancies in ZrO2: an ab initio Based Study. B.Malki, O.Le Bacq, A.Pasturel: Journal of Nuclear Materials, 2012, 429[1–3], 173–6