Covalent organic frameworks (COFs) are promising semiconductor photocatalysts but are still limited in overall water splitting mainly owing to a lack of clear design approaches with which to ameliorate catalytic activities. Here, we demonstrate a synergy of exciton dipole orientation and dynamic reactivity of COFs that enables water splitting for stoichiometric evolution of H₂ and O₂. The exciton dipole orientation is responsible for driving the spatial separation of photoinduced charges, while the dynamic reactivity of imine bonds of COFs with water and holes is proven for initiating water oxidation. Accordingly, a rationally designed BtS-COF with benzotrithiophene and sulfone units exhibits a much-improved performance in H₂ and O₂ evolution in neutral water under visible light. Its catalytic efficiency is even superior to some photocatalysts with metal-based water oxidation cocatalyst.

中文翻译：

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激子偶极子取向和动态反应性协同作用，可在共价有机框架中实现整体水分解


共价有机框架 （COF） 是很有前途的半导体光催化剂，但在整体水分解方面仍然受到限制，主要是由于缺乏明确的设计方法来改善催化活性。在这里，我们证明了激子偶极子取向和 COF 的动态反应性的协同作用，这使得 H₂ 和 O₂ 的化学计量演化能够分解水。激子偶极子取向负责驱动光生电荷的空间分离，而 COF 的亚胺键与水和空穴的动态反应性被证明可以引发水氧化。因此，在可见光下，具有苯并三噻吩和砜单元的合理设计的 BtS-COF 在中性水中表现出大大改善的 H₂ 和 O₂ 析出性能。其催化效率甚至优于一些带有金属基水氧化助催化剂的光催化剂。