Magnetic enhancement of oxygen evolution reaction performance of NiCo-spinel oxides

Abstract

Low-cost and high-efficiency transition metal oxide catalysts are desired for high-efficiency water splitting technology. An applying magnetic field (MF) enhancement method is presented to improve the oxygen evolution reaction (OER) performance of NiCo-spinel magnetic catalysts, the enhancement of OER performance depends on the applied MF strength and magnetic properties of catalysts. The maximum enhanced current density percentage of about 90.6%, 93.7%, and 70.1% are obtained by applying 105 mT MF in NiCo2O4, Ni1.5Co1.5O4, and Ni2CoO4, respectively. The enhanced performance originates from the improved intrinsic activity and facilitated mass transfer process. The MF decreases the activation energy, which then leads to the improvement of intrinsic activity. This work provides more basic data for further gaining into the enhanced mechanism by applying the MF, meanwhile, the strategy can be used to enhance the performances of other electrocatalysts.