Amorphous Bimetallic Metal–Organic Frameworks with an Optimized D-Band Center Enable Accelerating Oxygen Evolution Reaction
Hao Wu, Sirui Huang, Fan Ding, Yujie Ma, Qingxi Zhai, Yilun Ren, Yurong Yang, Lan Chen, Shaochun Tang, Xiangkang Meng
Abstract
Development of oxygen evolution reaction (OER) electrocatalysts with low cost and high performance is the key procedure in industrial electrolysis of water to produce hydrogen. Unfortunately, current reports heavily rely on empirical investigation and overlook the relationship between types of elements and the degree of amorphous, which hinders the design of amorphous metal–organic frameworks (MOFs) with high catalytic activity. Here, we prepared a series of bimetallic Fe-M-MOFs to explore the types of elements/degree of amorphous/catalytic property relationship. The amorphous FeNi-MOF containing crystalline nanostructures has the best OER performance and splendid stability. Additionally, density functional theory (DFT) demonstrates that benefiting from the strong coupling between Fe and Ni atoms, the d-band center of the active sites in FeNi-MOF (−0.92 eV) moves down compared to Fe-MOF (−1.24 eV), optimizing the *OOH intermediate toward rapid OER kinetics. This work provides a brand new approach to design efficient amorphous MOF electrocatalysts from the perspective of types of elements/degree of amorphous and regulation of the d-band center.