Electrochemical Exfoliation of the Two-Dimensional Conjugated Metal–Organic Framework for High-Performance Urea Electrooxidation

作者：Yong Li, Yu Xiang, Yu Fan, Guangxun Zhang, Songtao Zhang, Zhenyang Meng, Ziming Qiu, Yichun Su, Yangyang Sun, Nian‐Tzu Suen, Hsiao‐Chien Chen, Rongmei Zhu, Yecan Pi, Huan Pang · 发表于：ACS Nano · 年份：2025 · DOI：10.1021/acsnano.5c04006 · 被引用次数：27 · 研究领域：Conducting polymers and applications、Metal-Organic Frameworks: Synthesis and Applications、Electrocatalysts for Energy Conversion

Two-dimensional (2D) conjugated metal–organic frameworks (c-MOFs) have attracted extensive interest in electrochemical fields due to their inherent electrical conductivity. However, the severe interlayer stacking still poses barriers toward their potential applications. The reliable synthesis of ultrathin c-MOF nanosheets is crucial yet remains challenging. Herein, we demonstrate an electrochemical exfoliation approach to obtain ultrathin nanosheets from layer-stacked c-MOF crystals. Our results reveal the electric field-induced ion intercalation mechanism and provide a viable method for the synthesis of ultrathin M-HHTP (M = Ni, Cu, Co; HHTP = 2,3,6,7,10,11-hexahydroxytriphenylene) nanosheets. To prove utility, the obtained Ni-HHTP nanosheets as urea oxidation reaction (UOR) catalysts achieve an ultrahigh current density of 165.7 mA cm –2 at 1.35 V versus a reversible hydrogen electrode and nearly 100% selectivity of N-products. Experimental characterization and theoretical calculations reveal that the fully exposed square planar NiO 4 active centers effectively reduce the energy barrier of C–N bond cleavage for UOR and suppress the parasitic oxygen evolution reaction.