Developing robust nonprecious-metal electrocatalysts with high activity towards sluggish oxygen-evolution reaction is paramount for large-scale hydrogen production via electrochemical water splitting. Here we report that self-supported laminate composite electrodes composed of alternating nanoporous bimetallic iron-cobalt alloy/oxyhydroxide and cerium oxynitride (FeCo/CeO_2−xN_x) heterolamellas hold great promise as highly efficient electrocatalysts for alkaline oxygen-evolution reaction. By virtue of three-dimensional nanoporous architecture to offer abundant and accessible electroactive CoFeOOH/CeO_2−xN_x heterostructure interfaces through facilitating electron transfer and mass transport, nanoporous FeCo/CeO_2−xN_x composite electrodes exhibit superior oxygen-evolution electrocatalysis in 1 M KOH, with ultralow Tafel slope of ~33 mV dec⁻¹. At overpotential of as low as 360 mV, they reach >3900 mA cm⁻² and retain exceptional stability at ~1900 mA cm⁻² for >1000 h, outperforming commercial RuO₂ and some representative oxygen-evolution-reaction catalysts recently reported. These electrochemical properties make them attractive candidates as oxygen-evolution-reaction electrocatalysts in electrolysis of water for large-scale hydrogen generation.

开发对缓慢的析氧反应具有高活性的稳健非贵金属电催化剂对于通过电化学水分解大规模生产氢气至关重要。在这里，我们报道了由交替的纳米多孔双金属铁钴合金/羟基氧化物和氮氧化铈 (FeCo/CeO _{2− x} N _x ) 异质层片组成的自支撑层压复合电极作为碱性析氧反应的高效电催化剂具有广阔的前景。凭借三维纳米多孔结构，通过促进电子转移和传质，提供丰富且可接近的电活性 CoFeOOH/CeO _{2− x} N _x异质结构界面，纳米多孔 FeCo/CeO_{2− x} N _x复合电极在 1 M KOH 中表现出优异的析氧电催化作用，具有 ~33 mV dec ^-1的超低塔菲尔斜率。在低至 360 mV 的过电势下，它们达到 >3900 mA cm ^-2并在 ~1900 mA cm ^-2下保持出色的稳定性>1000 小时，优于商业 RuO ₂和最近报道的一些代表性的析氧反应催化剂。这些电化学特性使它们成为电解水大规模制氢中析氧反应电催化剂的有吸引力的候选者。