Role of defect-driven surface reconstructions in transition metal oxide electrocatalysis towards OER/ORR: A quantum-mechanical perspective

The catalytic activity of transition metal oxides (TMOs) for oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) is crucial for various electrochemical devices for energy conversion and storage. While electronic properties are considered the key factor influencing TMO reactivity, the specific surface chemistry has usually been neglected despite its pivotal influence on the catalytic features. In particular, punctual defects like vacancies and/or dopants can induce changes in the electronic and structural features of TMO surfaces, tuning the activity of the catalytic sites. Here, we provide a comprehensive overview of defect-driven surface reconstructions and their crucial role in boosting OER/ORR electrocatalysis in TMOs, reviewing the main findings from recent first-principles investigations.