Enhancing the Selective OH− Adsorption for Durable Alkaline Seawater Oxidation at Industrial Current Densities
Shangshu Hu, Jiao YANG, Yujuan Zhuang, Xueyao Li, Haibo Xu, Fuwang Hu, Zhishuo Yan, C. L. Liu, Jianmin Yu, Lishan Peng
Abstract
Abstract The oxygen evolution reaction (OER) in seawater electrolysis is pivotal for sustainable hydrogen production, yet severe chloride ion (Cl − )-induced corrosion at the anode critically limits catalyst durability. Herein, we design a heterostructured catalyst comprising NiFe-layered double hydroxide and Ce(OH)CO 3 (denoted as NiFe-LDH/Ce(OH)CO 3 ) that exhibits remarkable OER stability in alkaline-simulated seawater. Experimental results and density functional theory calculations reveal that Ce(OH)CO 3 incorporation modulates interfacial charge redistribution and enhances the Lewis acidity of Ni and Fe sites, thereby tuning the adsorption energetics of Cl − and OH − . Time-of-flight secondary ion mass spectrometry further confirms the preferential adsorption of OH − over Cl − , effectively suppressing Cl − -induced corrosion. As a result, NiFe-LDH/Ce(OH)CO 3 demonstrates exceptional long-term stability, maintaining continuous operation for over 450 h at 1 A cm −2 in alkaline seawater. When integrated into an anion exchange membrane electrolyzer, the catalyst achieves 1 A cm −2 at a low cell voltage of 1.92 V and operates stably for over 60 h. The system delivers an impressive energy efficiency of 68.59% in alkaline-simulated seawater, corresponding to a hydrogen production cost as low as $0.97 per gasoline gallon equivalent at 500 mA cm −2 . Graphical abstract The integration of Ce(OH)CO 3 with NiFe-LDH enhances the Lewis acidity of Ni and Fe, enabling preferential OH - adsorption while eff ectively suppressing chlorine corrosion, and ultimately achieving durable seawater oxidation atindustrial current densities.