Fe-MOF-235 as an Efficient and Stable Electrocatalyst for the Oxygen Evolution Reaction

Abstract Oxygen evolution reaction (OER) is studied on four kinds of Fe-based MOFs (Fe-MOF-235, Fe-MIL-101, Fe-MIL-88B and Fe-MIL-53) synthesized by solvothermal method using FeCl3·6H2O and terephthalic acid as precursors. Among them, Fe-MOF-235 exhibited optimal activity with the overpotential of 255 mV at a current density of 10 mA·cm−2, and a small Tafel slope of 33.1 mV·dec−1. However, OER activity of the catalyst decreases, when the skeleton structure of Fe-MOF-235 is destroyed after calcination. It is found that the outstanding OER performance of Fe-MOF-235 may be due to abundant active sites and faster charge transport kinetics afforded by the complete skeleton structure of Fe-MOF-235, and it also shows excellent stability during 70 h electrochemical testing. Therefore, Fe-MOF-235 can be directly used as an efficient OER catalyst.