Specific role of transient O−(s) at Mg(0001) surfaces in activation of ammonia by dioxygen and nitrous oxide
Specific role of transient O−(s) at Mg(0001) surfaces in activation of ammonia by dioxygen and nitrous oxide
复制标题
Mg(0001) 表面瞬态 O−(s) 在分子氧和一氧化二氮活化氨中的具体作用
作者：
C. Au;M. W. Roberts
已经确定 1-3 金属表面化学吸附的氧可以激活原本不反应的分子，如激活 S-H、N-H、O-H 和 C-H 键。我们现在将这些研究扩展到涉及共吸附分子的更复杂的系统，希望对多相催化剂的机理有一些启发。我们之前已经建立了吸附在 Zn(0001) 表面上的非反应性分子水在与一氧化氮共吸附时被激活的机制，并证明了在 295 K 的原子级清洁的 Mg(0001) 表面上与一氧化氮共吸附的氨中的 N-H 活化（图 1a 和参考文献 5）。活化归因于一氧化氮解离化学吸附中产生的表面氧。在这里，我们确定了所涉及的“氧”物种的性质并揭示了分子步骤的细节。
It has been established1–3 that oxygen chemisorbed at a metal surface can activate an otherwise unreactive molecule, as in the activation of S–H, N–H, O–H and C–H bonds. We have now extended these studies to more complex systems involving coadsorbed molecules in the hope of throwing some light on the mechanisms of heterogeneous catalysts. We have previously established the mechanisms by which unreactive molecular water, adsorbed on a Zn(0001) surface, is activated when co-adsorbed with nitric oxide4, and have demonstrated N–H activation in ammonia co-adsorbed with nitric oxide at an atomically clean Mg(0001) surface at 295 K (Fig. la and ref. 5). Activation was attributed to surface oxygen generated in the dissociative chemisorption of nitric oxide. Here we establish the nature of the ‘oxygen’ species involved and reveal details of the molecular steps.