Enhanced Oxygen Evolution of a Magnetic Catalyst by Regulating Intrinsic Magnetism

The promotion of magnetic field on catalytic performance has attracted extensive attention. However, little research has been reported on the performance of the oxygen evolution reaction (OER) for the modulating intrinsic magnetism of the catalyst under a magnetic field. Herein, we adjusted the intrinsic magnetism of the Co_xNi_1-xFe₂O₄-nanosheet by adjusting the ratio of Co and Ni, and researched the relationship between the OER activity and the intrinsic magnetism. The results indicate that the CoFe₂O₄-nanosheet has the most OER activity increases in the magnetic field due to the optimal intrinsic magnetism. The required overpotential of CoFe₂O₄-nanosheet@NF to reach a current density of 10 mA cm^-2 was reduced by 21 mV under about 100 mT magnetic field compared with no magnetic field, and the degree of improvement of OER activity of different magnetic catalysts in the same magnetic field is positively correlated with the intrinsic magnetism of the catalyst. Therefore, magnetic field assistance provides a new, effective, and general strategy to improve the activity of electrodes for water splitting.