Two-dimensional conductive metal-organic frameworks with dual metal sites toward the electrochemical oxygen evolution reaction

Conductive metal-organic frameworks (MOFs) are relevant as active materials for many applications, including electrocatalysis, chemiresistive sensing, and energy storage. However, the structure-activity relationship toward electrocatalysis in conductive MOFs needs to be further explored. Herein, a new strategy of electronic structure modification is proposed by introducing phthalocyanine with extra metal sites into conductive MOFs. Density Functional Theory (DFT) calculations predict that these MOFs possess excellent conductivity with a narrow band-gap. Electrochemical tests and d-band center calculations confirm the highest activity of NiPc-Ni among the MOFs, indicating that both Ni-N-4 and Ni-O-4 sites are active for the OER. Moreover, PDOS analysis and TOF calculations indicate that the electronic structure interaction between Ni-O-4 and Ni-N-4 sites improves their intrinsic OER activity. This work provides an effective strategy for modulating the electronic structure and revealing the structure-activity relationship in 2D conductive MOFs toward electrocatalysis.