Mechanisms of water photooxidation at n-TiO2 rutile single crystal oriented electrodes under UV illumination in competition with photocorrosion

► A deeper understanding of photoelectrochemical water splitting in competition with photocorrosion at rutile electrodes is offered. ► Photogeneration of bridging oxygen vacancies is a key step for water splitting at rutile electrodes. ► The photocatalytic activity of rutile electrodes for water splitting is analyzed in terms of bridging oxygen atoms arrangement. ► A sequential description of reaction steps involved in photoelectrochemical water splitting at rutile electrodes is presented.