Pre‐Adsorbed H‐Assisted N2 Activation on Single‐Atom Cadmium‐O5 Decorated In2O3 for Efficient NH3 Electrosynthesis

Abstract The electrocatalytic nitrogen reduction reaction (NRR) provides a promising avenue for sustainable and decentralized green ammonia (NH 3 ) synthesis. To promote the NRR, the design and synthesis of efficient electrocatalysts with an elucidated reaction mechanism is critically important. Here, surface hydrogenation‐facilitated NRR is demonstrated to yield NH 3 at low overpotentials on oxygen‐deficient In 2 O 3 plates decorated with single atom CdO 5 that have a weak N 2 ‐binding capability. Adsorbed * H is calculated to be first produced via the Volmer reaction (H 2 O + e − → * H + OH − ) and then reacts with dissolved N 2 to generate * N 2 H 2 , which is likely the rate determining step (RDS) of the whole process. Cd atoms and oxygen vacancies in In 2 O 3 jointly enhance the activation of N 2 and accelerate the RDS, boosting the NRR. An NH 3 production rate of as high as 57.5 µg h −1 mg cat −1 is attained at a mild potential, which is retained to a large extent even after 44 h of continuous polarization.