Electron-Rich Co Sites via Heterointerface Engineering Enable Cl – Repulsion and OH – Affinity for Efficient Seawater Hydrogen Evolution

作者：Kun Lang, Yuanyingxue Gao, Xudong Xiao, Qi Li, Mingyang Liu, Jianan Liu, Huiquan Gu, Wei Wu, Huiyuan Meng, Baojiang Jiang · 发表于：ACS Applied Materials & Interfaces · 年份：2025 · DOI：10.1021/acsami.5c12786 · 被引用次数：4 · 研究领域：Electrocatalysts for Energy Conversion、MXene and MAX Phase Materials、Fuel Cells and Related Materials

Seawater electrolysis offers a sustainable pathway for green hydrogen production, but chloride-induced side reactions, particularly chlorine evolution (ClER), limit the stability and efficiency of catalysts. Based on an interface-engineering strategy, a bifunctional CoP–MXene electrocatalyst was designed and fabricated, in which electrons are transferred from the Ti sites of the MXene support to the adjacent Co active centers of CoP. This directional electron donation modulates the Co electronic structure, generating electron-rich Co sites that effectively suppress Cl – adsorption via electronic repulsion while preserving the OH – reaction pathways through favorable proton–electron coupling. X-ray absorption fine structure (XAFS) spectroscopy, in situ Raman spectroscopy, and density functional theory (DFT) calculations further validate this electron modulation mechanism. In 1 M KOH electrolyte, CoP–MXene achieves a hydrogen evolution reaction (HER) overpotential of only 93 mV at 10 mA cm –2 and an oxygen evolution reaction (OER) current density of 50 mA cm –2 at 346 mV. In alkaline seawater, CoP–MXene exhibits exceptional HER performance (10 mA cm –2 @ 101 mV). Moreover, in an anion exchange membrane (AEM) electrolyzer (at 2 A cm –2 current density), the catalyst maintains over 500 h of stability in seawater with only 8.5% current decay, significantly outperforming the control samples. This study provides a new design strategy for the development of chloride-resistant electro...