Tang Zhun, Chen Delun, Li Weiwei, Li Hai, Tu Jinchun, Zhang Xiaolin, Wang Bingrong, Yu Rentong
School of Materials Science and Engineering, State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, Hainan 570228, China.
College of Science, Laboratory of Child Cognition & Behavior Development of Hainan Province, Qiongtai Normal University, Haikou 571127, China.
J Colloid Interface Sci. 2025 May;685:361-370. doi: 10.1016/j.jcis.2025.01.133. Epub 2025 Jan 19.
Emerging of the lattice oxygen mechanism (LOM) provides a new opportunity for enhancing oxygen evolution reaction (OER) activity. However, its stability suffers from metal cation dissolution and lattice oxygen anionic redox chemistry. In this paper, carbon dots (CDs)-modified nickel-iron MOF (Metal-Organic Framework) nanosheets (NiFe-BDC/CDs) were prepared for efficient OER electrocatalysis. The introduction of CDs promotes the hybridization of the O 2p band in the MOF with the metal 3d band near the Fermi level, leading to improved involvement of lattice oxygen in the oxygen evolution reaction. Additionally, C-M bonds formed between CDs and metal sites in MOF enhanced the stability of electrocatalyst. As results, the prepared NiFe-BDC/CDs electrodes demonstrated a current density of 100 mA cm at overpotentials of 235 and 250 mV in alkaline freshwater and alkaline seawater, respectively, and a remarkable stability in alkaline seawater at 500 mA cm for >100 h. This study provides a simple and versatile strategy for the design of OER electrocatalysts with highly active transition metal-based MOFs.
晶格氧机制（LOM）的出现为提高析氧反应（OER）活性提供了新的机遇。然而，其稳定性受到金属阳离子溶解和晶格氧阴离子氧化还原化学的影响。本文制备了碳点（CDs）修饰的镍铁金属有机框架（MOF）纳米片（NiFe-BDC/CDs）用于高效的OER电催化。CDs的引入促进了MOF中O 2p能带与费米能级附近金属3d能带的杂化，从而提高了晶格氧在析氧反应中的参与度。此外，CDs与MOF中的金属位点之间形成的C-M键增强了电催化剂的稳定性。结果表明，制备的NiFe-BDC/CDs电极在碱性淡水和碱性海水中，过电位分别为235和250 mV时，电流密度可达100 mA cm ，并且在碱性海水中500 mA cm 下具有超过100 h的显著稳定性。本研究为设计具有高活性过渡金属基MOF的OER电催化剂提供了一种简单通用的策略。
