Electrochemical water splitting is restrained by the sluggish oxygen evolution reaction (OER) due to the four-proton-coupled electron transfer. One key strategy for efficient large-scale production of hydrogen by water splitting is to design an electrode structure with low OER overpotential. Herein, a coaxial three-layer structure for the OER electrode is constructed by electroplating Ni on Cu mesh and then loading (Ni,Fe)O_xH_y catalyst via a modified solvothermal method. The obtained coaxial three-layer (Ni,Fe)O_xH_y/Ni/Cu mesh electrode exhibits an excellent OER performance with the overpotentials of 199 and 250 mV at 10 and 50 mA cm⁻² and stability for over 72 h in 1 M KOH. The plated Ni layer is critical for the coaxial three-layer (Ni,Fe)O_xH_y/Ni/Cu mesh structure since it improves its stability by preventing Cu from corroding and meanwhile enhances the adhesive strength of (Ni,Fe)O_xH_y to the substrate because of its poor crystallinity, which facilitates charge transfer and leads to the extremely low overpotentials. Compared with Ni foam and Ni mesh, Cu mesh is more suitable for high production rate and large-area water splitting at large overpotentials because of its excellent conductivity and lower series electric resistance (R_s). Together with the extremely low cost of Cu mesh, the present coaxial three-layer (Ni,Fe)O_xH_y/Ni/Cu mesh electrode is promising for future industrial application.

中文翻译：

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同轴三层（Ni，Fe）OxHy / Ni / Cu网状电极：对水电解具有出色的析氧反应活性

由于四质子偶联的电子转移，缓慢的氧气析出反应（OER）抑制了电化学水的分解。通过水分解有效大规模生产氢的一种关键策略是设计一种具有低OER过电位的电极结构。在此，用于OER电极的同轴三层结构是通过在铜网上电镀镍，然后通过改进的溶剂热法加载（Ni，Fe）O _x H _y催化剂而构建的。所获得的同轴三层（Ni，Fe）O _x H _y / Ni / Cu网状电极表现出优异的OER性能，在10和50 mA cm ^-2时的过电势为199和250 mV在1 M KOH中的稳定性和稳定性超过72小时。镀镍层对于同轴三层（Ni，Fe）O _x H _y / Ni / Cu网状结构至关重要，因为它通过防止Cu腐蚀而提高了其稳定性，同时增强了（Ni，Fe）O的粘合强度_x H _y对基材的结晶性差，这有利于电荷转移并导致极低的过电势。与镍泡沫和镍网相比，铜网具有优异的电导率和较低的串联电阻（R _s），因此更适合于高生产率和大电势下的大面积水分解。加上极低廉的铜网成本，目前的同轴三层（Ni，Fe）O_x H _y / Ni / Cu网状电极有望用于未来的工业应用。