A bimetallic NiFe MOF directly grown on NiFe foam as an oxygen evolution reaction catalyst

Transition metal NiFe-based MOFs have attracted much attention as catalysts for electrocatalytic reactions due to their tunable electronic structure, enormous specific surface area, and abundant pore structure. However, MOF materials generally suffer from poor electrical conductivity. To solve this problem, MOFs can be grown in situ on substrates with good electrical conductivity. Another key issue to be solved is the tight connection of MOFs with the substrate, which will directly affect the cycling stability of MOF catalysts and their ability to withstand high current density. Based on this, in this study, the in situ growth of the NiFe-MOF on a nickel–iron foam (NFF) substrate using NaCl as the corrosive agent enables close contact between the generated NiFe-MOF and NFF. Electrocatalytic OER tests confirm that the prepared NiFe-MOF/NFF catalyst has an overpotential of 233.0 mV at 10 mA cm−2, which is superior to those of the corresponding Ni-MOF/NFF and Fe-MOF/NFF. Ni and Fe collaborated in concert to boost the performance of electrocatalysts. Additionally, the catalyst can also maintain good cycling stability for 21 h without obvious current decay. The implementation of this study opens a new research direction for the practical application of MOF catalysts in electrocatalysis.