Magnetic field- assisted synthesis of iron-doped cobalt oxide with abundant oxygen defects as an electrocatalyst for oxygen evolution reaction

The oxygen evolution reaction (OER) is a critical step in the overall process of water electrolysis, and developing low-cost, high-performance OER electrocatalysts is essential for achieving efficient energy conversion. In this work, iron-doped cobalt oxide was successfully prepared by a magnetic field-assisted synthesis strategy, and the material exhibited excellent catalytic performance in the oxygen evolution reaction. Specifically, the overpotential of M-Fe-Co3O4 at a current density of 10 mA/cm2 is only 297 mV, and the Tafel slope is 74 mV/dec, outperforming Fe-Co3O4 synthesized under magnetic field-free conditions. By analyzing X-ray photoelectron spectroscopy, Raman spectroscopy and UV photoelectron spectroscopy, it was found that this improvement in catalytic activity mainly originated from the changes in the electronic structure of iron-doped cobalt oxide, with an increase in the content of oxygen vacancy and an increase in electrical conductivity. This work highlights the important role of magnetic fields in modulating the electronic structure of materials, demonstrates the potential of using magnetic fields to develop high-performance catalysts, and offers new possibilities for future material design and development of energy conversion technologies.