Niu, Q.Gao, F.-Y.Sun, X.Zheng, Y.Qiao, S.-Z.2025-08-082025-08-082025Advanced Functional Materials, 2025; 2504872-1-2504872-71616-301X1616-3028https://hdl.handle.net/2440/146646OnlinePublIn water electrolysis, the long-term stability of anodes is compromised by their degradation under oxidative conditions. This issue becomes more pronounced in seawater electrolysis, where the natural chloride ion (Cl¯) induces the chlorine evolution reaction (ClER) to produce corrosive byproducts. Herein, a series of small organic molecules (SOMs), featuring an aromatic carbon ring with para-positioned carbonyl groups, are integrated with the conventional nickel-iron (Ni-Fe) based anode. This integration triggers a unique electron buffering effect to address anode degradation in natural seawater-based electrolytes. It is found that preferential adsorption of Cl¯ onto SOMs prevents its direct interaction with metal active sites. Furthermore, SOM-Cl serving as an electron buffering group significantly reduces the dissolution of Fe sites under the highly oxidative environment. As a result, the SOM-Cl-engineered anode enhances oxygen evolution activity by ≈1.7 times in seawater compared to pure water. In addition, the rationally designed anode works stably for over 200 h at a high current density of 1.3 A cm¯² in an alkaline seawater electrolyzer (ASE).en© 2025 The Author(s). Advanced Functional Materials published by Wiley-VCH GmbH. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.ampere-level current density; Cl-mediated electron buffering; oxygen evolution reaction; seawater electrolysis; small organic moleculesJournal article10.1002/adfm.202504872736204Niu, Q. [0000-0003-0991-7838]Gao, F.-Y. [0000-0002-3811-7509]Sun, X. [0000-0002-3057-5580]Zheng, Y. [0000-0002-2411-8041]Qiao, S.-Z. [0000-0002-1220-1761] [0000-0002-4568-8422]