Deciphering NH3 Adsorption Kinetics in Ternary Ni–Cu–Fe Oxyhydroxide toward Efficient Ammonia Oxidation Reaction

Abstract Developing efficient catalysts for the ammonia oxidation reaction (AOR) is crucial for NH 3 utilization as a large‐scale energy carrier. This work reports a promising Ni–Cu–Fe–OOH material for ammonia oxidation, and density functional theory is used to investigate the AOR mechanism. It is revealed that the oxygen‐atoms bonded with the metal‐atom on the surface of electrode play an important role in AOR. By codoping Cu and Fe, the electron distribution around the oxygen‐atom is affected, which helps to promote the occurrence of ammonia oxidation. The Ni–Cu–Fe–OOH material delivers one of the highest ammonia removal efficiency to date of ≈90% after 12 h. In addition, ≈55% of the initial ammonia is successfully degraded after 24 h in high ammonia concentration. Thus, this work reveals the mechanism of AOR that can provide new ideas to tailor more powerful and updated catalysts in the future.