Wenji Shao1, Yijie Wu1, Wanqing Yu, Tianjing Zhang, Yi Tao, Yitong Zhou, Anqi Dong*, Hao Zhang*, Xuhui Sun*

Cite this article: https://doi.org/10.1016/j.cjsc.2026.101104

Publication date:

Keywords: Oxygen evolution reaction; NiFe-LDH; Molybdate engineering; Chloride resistance; Interlayer engineering; In-situ spectroscopy

ABSTRACT

Developing robust anodes for alkaline seawater electrolysis requires not only high oxygen evolution reaction (OER) activity, but also strong catalysts-substrate integration and resistance to chloride-induced corrosion under prolonged operation. Herein, we report a Mo-modified NiFe-LDH directly grown on Ni foam through an NH4F-assisted hydrothermal synthesis strategy, which simultaneously strengthens interfacial integration and regulates the local surface chemistry. Structural characterizations reveal that NH4F induces the formation of a dense interlayer between the active catalyst and the conductive substrate, while Mo is incorporated as highly dispersed MoO42- species linked to Ni/Fe centers through Mo-O-Ni(Fe) coordination. This structural design not only optimizes the electronic environment of the catalytic sites and promotes OER kinetics, but also creates a chloride-resistant interfacial environment. As a result, the optimized Mo-NiFe-LDH electrode exhibits excellent OER activity, requiring a low overpotentials of 238 mV to deliver 100 mA cm-2 in simulated alkaline seawater. More importantly, it maintains stable operation at 200 mA cm-2 for over 3500 h in alkaline seawater with an ultralow degradation rate of 8.4 μV h-1. In-situ spectroscopic results provide direct mechanistic evidences that the NiFe-LDH dynamically reconstructs to the active Ni(Fe)OOH phase during OER, whereas MoO42- remains structurally persistent and effectively inhibits the formation of chlorine-containing species. This work highlights the importance of simultaneously engineering catalysts-substrate integration and anti-chloride interfacial chemistry, and offers a practical strategy for designing high-performance anodes for long-term seawater electrolysis.