Surface reconstruction and structural transformation of two-dimensional Ni-Fe MOFs for oxygen evolution in seawater media

作者：Liyuan Xiao, Xue Bai, Jingyi Han, Tianmi Tang, Siyu Chen, Hui Qi, Changmin Hou, Fuquan Bai, Zhenlü Wang, Jingqi Guan · 发表于：Nano Research · 年份：2023 · DOI：10.1007/s12274-023-6088-x · 被引用次数：86 · 研究领域：Electrocatalysts for Energy Conversion、Advanced Memory and Neural Computing、Advanced Nanomaterials in Catalysis

As a four-electron transfer reaction, oxygen evolution reaction (OER) is limited by large overpotential and slow kinetics. Here, we in-situ synthesized two-dimensional (2D) Ni-Fe metal-organic framework nanosheets on nickel foam (Ni x Fe-TPA/NF, TPA = terephthalic acid) for oxygen evolution in alkaline and alkaline seawater electrolytes. In 1 M KOH, Ni 3 Fe-TPA/NF shows a low overpotential ( η 10 ) of 189 mV at 10 mA·cm −2 and an ultra-low overpotential of only 260 mV at 500 mA·cm −2 . In alkaline seawater, Ni 3 Fe-TPA/NF still provides impressive OER performance, with an η 10 of 265 mV. In-situ Raman characterization results show that the phase transition occurs during the OER, and Ni 3 FeOOH with more oxygen vacancies is in-situ formed, reducing the OER energy barrier. Density functional theory (DFT) reveals that the synergy between Ni and Fe reduces the energy barrier and accelerates the rate-determining step. In addition, the ultra-thin 2D sheet structure and the close combination of Ni 3 FeOOH and highly conductive NF support ensure the high catalytic OER activity. Therefore, the surface reconstruction and structural modification strategy can be used to design and prepare high-performance OER electrocatalysts for energy-related applications.