An understanding of the deactivation mechanism of Pt electrocatalysis towards the ammonia oxidation reaction (AOR) to dinitrogen is key to the successful introduction of the nitrogen energy cycle, which can be used as a source of hydrogen fuels. Herein, we study AOR electrocatalysis on NO_x-adsorbed polycrystalline Pt electrodes, i.e. NO, NO₂⁻ and NO₃⁻, and find that all the NO_x species can significantly reduce the catalytic activity of Pt. Combined stationary/transient voltammograms reveal that the poisonous NO_x species are produced by NH₃ oxidation on the bare Pt surface, but the adsorbed NO_x species can be transformed to N₂ by the Langmuir–Hinshelwood mechanism with *NO as a key intermediate.

了解Pt电催化氨氧化反应（AOR）生成二氮的失活机理，是成功引入氮能循环的关键，该循环可用作氢燃料。在此，我们研究AOR电催化的NO _X -adsorbed多晶铂电极，即NO，NO ₂ ^-和NO ₃ ^- ，发现所有的NO _X种可以显著降低铂的催化活性。合并的静止/短暂伏安揭示出有毒NO _X由NH产生物种₃氧化裸铂表面上，但NO吸附_X物种可以转化为N₂由Langmuir-Hinshelwood机理研究，其中* NO为关键中间体。