Oxygen‐Doped γ‐Mo2N as High‐Performance Catalyst for Ammonia Decomposition

Abstract γ‐Mo 2 N catalysts exhibit excellent activity and stability in ammonia decomposition reactions. However, the influence of oxygen on its activity is still unknown. In this work, two γ‐Mo 2 N catalysts with different oxygen content are synthesized using temperature‐programmed nitridation of α‐MoO 3 . The γ‐Mo 2 N catalysts are highly oxidized and their ammonia decomposition performance is closely related to their oxygen content. The activity of γ‐Mo 2 N with high oxygen content (HO‐γ‐Mo 2 N) is much higher, whose H 2 formation rate at 550 °C is 3.3 times higher than the γ‐Mo 2 N with low oxygen content (LO‐γ‐Mo 2 N). This is mainly attributed to two aspects: on the one hand, the higher valence state of Mo in the HO‐γ‐Mo 2 N leads to stronger Mo─NH 3 bonds, which promotes the adsorption and activation of NH 3 . On the other hand, the H generated by N─H bond breaking is more easily migrated to O, which avoids excessive H occupying the γ‐Mo 2 N active sites and alleviates the negative effect of hydrogen poisoning.