Liu Yizhe, Li Xintong, Sun Qidi, Wang Zilong, Huang Wei-Hsiang, Guo Xuyun, Fan Zhanxi, Ye Ruquan, Zhu Ye, Chueh Chu-Chen, Chen Chi-Liang, Zhu Zonglong
Department of Chemistry, City University of Hong Kong, Kowloon, 999077, Hong Kong.
Siyuan Laboratory, Guangdong Provincial Engineering Technology Research Center of Vacuum Coating Technologies and New Energy Materials, Department of Physics, Jinan University, Guangzhou, Guangdong, 510632, P. R. China.
Small. 2022 Jul;18(26):e2201076. doi: 10.1002/smll.202201076. Epub 2022 May 31.
The oxygen evolution reaction (OER) is crucial to electrochemical hydrogen production. However, designing and fabricating efficient electrocatalysts still remains challenging. By confinedly coordinating organic ligands with metal species in layered double hydroxides (LDHs), an innovative LDHs-assisted approach is developed to facilely synthesize freestanding bimetallic 2D metal-organic framework nanosheets (2D MOF NSs), preserving the metallic components and activities in OER. Furthermore, the research has demonstrated that the incorporation of carboxyl organic ligands coordinated with metal atoms as proton transfer mediators endow 2D MOF NSs with efficient proton transfer during the electrochemical OH → O transition. These freestanding NiFe-2D MOF NSs require a small overpotential of 260 mV for a current density of 10 mA cm . When this strategy is applied to LDH nanosheets grown on nickel foam, the overpotential can be reduced to 221 mV. This outstanding OER activity supports the capability of multimetallic organic frameworks for the rational design of water oxidation electrocatalysts. This strategy provides a universal path to the synthesis of 2D MOF NSs that can be used as electrocatalysts directly.
析氧反应（OER）对电化学制氢至关重要。然而，设计和制造高效的电催化剂仍然具有挑战性。通过将有机配体与层状双氢氧化物（LDHs）中的金属物种进行限域配位，开发了一种创新的LDHs辅助方法，以轻松合成独立的双金属二维金属有机框架纳米片（2D MOF NSs），并保留OER中的金属成分和活性。此外，研究表明，作为质子转移介质的与金属原子配位的羧基有机配体的掺入，使2D MOF NSs在电化学OH→O转变过程中具有高效的质子转移能力。这些独立的NiFe-2D MOF NSs在电流密度为10 mA cm时需要260 mV的小过电位。当该策略应用于在泡沫镍上生长的LDH纳米片时，过电位可降至221 mV。这种出色的OER活性支持了多金属有机框架对水氧化电催化剂进行合理设计的能力。该策略为合成可直接用作电催化剂的2D MOF NSs提供了一条通用途径。
