Developing non‐noble metal electrocatalysts with high catalytic activity and stability is very important for practical water splitting technology. Herein, electrocatalytically active, bifunctional, and durable electrodes, are reported where NiCo₂S₄ nanosheets deposited onto nitrogen‐incorporated reduced graphene oxide (N‐rGO) are assembled onto 3D Ni foam. These freestanding binder‐free electrodes exhibit excellent bifunctional catalytic activity for both hydrogen evolution and oxygen evolution reactions in alkaline condition, as well as overall water splitting reaction measured in a two‐electrode configuration. The cell voltage is as low as 1.63 V to achieve a current density of 10 mA cm⁻² and this value is well preserved with negligible overpotential for more than 50 h. The results open a door to design bifunctional durable electrode based on non‐noble metals for practical alkaline water electrolyzers.

中文翻译：

---

垂直排列的NiCo2S4纳米片沉积在N掺杂的石墨烯上，用于双功能和耐用的总水分解电极

开发具有高催化活性和稳定性的非贵金属电催化剂对于实用的水分解技术非常重要。本文报道了电催化活性，双功能和耐用电极，其中沉积在掺氮还原氧化石墨烯（N-rGO）上的NiCo ₂ S ₄纳米片被组装到3D Ni泡沫上。这些独立的无粘结剂电极对碱性条件下的氢气释放和氧气逸出反应以及在双电极配置下测得的总水分解反应均具有出色的双功能催化活性。电池电压低至1.63 V，以实现10 mA cm ^-2的电流密度该值保存良好，且超电位可以忽略不计超过50小时。结果为设计用于实用碱性水电解槽的基于非贵金属的双功能耐用电极打开了一扇门。