Enhancing the Understanding of the Oxygen Evolution Reaction on Bimetallic Two-Dimensional MOFs through Theoretical Investigation

Bimetallic two-dimensional (2D) conjugated phthalocyanine-based metal-organic frameworks (MOFs) show excellent electrocatalytic activity due to the advantages of a well-regulated electronic structure and excellent conductivity. However, the application of the bimetallic 2D MOFs in the oxygen evolution reaction (OER) is still in its infancy, and the intrinsic structure-activity relationships are ambiguous. Here, a theoretical study was carried out to investigate the potential of two cutting-edge carbon dioxide reduction electrocatalysts, CuPc-ZnO4 and CoPc-CuO4, for OER and clarify their intrinsic features. It is concluded that compared with the reported OER catalyst NiPc-NiO4, CoPc-CuO4 is more favorable while CuPc-ZnO4 is not. The favorable CoPc site is attributed to a stronger O* interaction effect relative to OH* rather than the interaction with individual intermediates. Originally, it is revealed that besides the electronic structure of the d-band center, the structural flexibility of catalytic sites is also an important factor regulating the catalytic activity. The results enhance the understanding of OER activity on bimetallic 2D MOFs.