Engineering a reaction pathway to harmonize the competition between nitrogen reduction reaction (NRR) and hydrogen evolution reaction (HER) is an active strategy toward efficient ammonia synthesis. Herein, we insert a “hydrogen state switching” reaction between the NRR and HER in ammonia synthesis. H₂ from HER in NH₂-MIL125 core is captured by the Ni nanoparticles on polydopamine shell and switched into adsorbed-state *H species, which are then transferred back to NH₂-MIL125 core via NiO to react with nitrogen and produce NH₃. By manipulating the reaction pathway of hydrogen generation-state switching-transfer-utilization, HER can supply the required hydrogen for NRR. Accordingly, our photocatalyst achieved the NH₃ yield and selectivity of 817 μmol g^–1 h^–1 and 99.8% in NRR, respectively, superior to those of most state-of-the-art photocatalysts. Our strategy, as “transforming-competition-into-cooperation” strategy, is applicable for many complex reaction systems.

中文翻译：

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协调NRR和HER之间竞争的工程反应途径以实现高效光催化氨合成


设计一条反应途径来协调氮还原反应（NRR）和析氢反应（HER）之间的竞争是实现高效氨合成的积极策略。在这里，我们在氨合成中的NRR和HER之间插入了“氢态转换”反应。 NH ₂ 中 HER 中的 H ₂ -MIL125 核心被聚多巴胺壳上的 Ni 纳米粒子捕获，并转化为吸附态 *H 物质，然后转移回 NH ₂ -MIL125核心通过NiO与氮气反应生成NH ₃ 。通过操控氢气生成-状态切换-转移-利用的反应路径，HER可以为NRR提供所需的氢气。因此，我们的光催化剂的NH ₃ 产率和选择性分别为817 μmol g ^–1 h ^–1 和99.8％的NRR，优于大多数国家的水平最先进的光催化剂。我们的策略是“变竞争为合作”策略，适用于许多复杂的反应系统。