Electrochemically converting water into oxygen/hydrogen gas is ideal for high-density renewable energy storage in which robust electrocatalysts for efficient oxygen evolution play crucial roles. To date, however, electrocatalysts with long-term stability have remained elusive. Here we report that single-crystal Co3O4 nanocube underlay with a thin CoO layer results in a high-performance and high-stability electrocatalyst in oxygen evolution reaction. An in situ X-ray diffraction method is developed to observe a strong correlation between the initialization of the oxygen evolution and the formation of active metal oxyhydroxide phase. The lattice of skin layer adapts to the structure of the active phase, which enables a reversible facile structural change that facilitates the chemical reactions without breaking the scaffold of the electrocatalysts. The single-crystal nanocube electrode exhibits stable, continuous oxygen evolution for >1,000 h. This robust stability is attributed to the complementary nature of defect-free single-crystal electrocatalyst and the reversible adapting layer.

中文翻译：

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可逆的适应层产生用于氧释放的坚固的单晶电催化剂。

将水电化学转化为氧气/氢气是高密度可再生能源存储的理想选择，在这种存储中，有效释放氧气的坚固电催化剂起着至关重要的作用。然而，迄今为止，具有长期稳定性的电催化剂仍然难以捉摸。在这里，我们报道了具有薄CoO层的单晶Co3O4纳米立方衬底，在氧气析出反应中产生了高性能和高稳定性的电催化剂。开发了一种原位X射线衍射方法，以观察氧释放的初始化与活性金属羟基氧化物相的形成之间的强烈相关性。表皮层的晶格适应活性相的结构，这使得可逆的易变结构变化能够促进化学反应，而不会破坏电催化剂的支架。单晶纳米立方体电极在> 1,000小时内表现出稳定，连续的氧气析出。这种坚固的稳定性归因于无缺陷单晶电催化剂和可逆适应层的互补性。