Expanded Negative Electrostatic Network-Assisted Seawater Oxidation and High-Salinity Seawater Reutilization

作者：Jie Liang, Zhengwei Cai, Zixiao Li, Meiqi Geng, Hefeng Wang, Zhi-Qiang Wang, Tingshuai Li, Tongwei Wu, Fengming Luo, Xuping Sun, Bo Tang · 发表于：ACS Nano · 年份：2025 · DOI：10.1021/acsnano.4c14502 · 被引用次数：59 · 研究领域：Electrocatalysts for Energy Conversion、Advanced Photocatalysis Techniques、Advanced battery technologies research

Coastal/offshore renewable energy sources combined with seawater splitting offer an attractive means for large-scale H 2 electrosynthesis in the future. However, designing anodes proves rather challenging, as surface chlorine chemistry must be blocked, particularly at high current densities ( J ). Additionally, waste seawater with increased salinity produced after long-term electrolysis would impair the whole process sustainability. Here, we convert seawater to O 2 selectively, on hydroxides, by building phytate-based expanded negative electrostatic networks (ENENs) with electrostatically repulsive capacities and higher negative charge coverage ranges than those of common inorganic polyatomic anions. With surface ENENs, even typically unstable CoFe hydroxides perform nicely toward alkaline seawater oxidation at activities of >1 A cm –2 . CoFe hydroxides with phytate-based ENENs exhibit prolonged lifespans of 1000 h at J of 1 A cm –2 and 900 h at J of 2 A cm –2 and thus rival the best seawater oxidation anodes. Direct introduction of trace phytates to seawater weakens corrosion tendency on conventional CoFe hydroxides as well, extending the life of hydroxides by ∼28 times at J of 2 A cm –2 . A wide range of materials all obtain prolonged lifetimes in the presence of ENENs, validating universal applicability. Mechanisms are studied using theoretical computations under working conditions and ex situ / in situ characterizations. We demonstrate a potentially viable way to sustaina...