Magnetic field improvement of hydrogen evolution reaction in MOF-derived NiCo2S4 nanostructure

Great efforts have been made to increase the hydrogen evolution reaction (HER) of electrocatalysts by porous structure, dopants and heterostructure engineering. However, the HER catalytic properties have entered a bottleneck stage only depend on these methods. As a contact-free field to enhance the electrochemical reactions, magnetic field has attracted extensive attention recently. In this study, the Ni-MOF derived NiCo2S4 nanostructures are prepared via a facile hydrothermal preparation. By applying an external magnetic field, the NiCo2S4 delivers much better HER performance than in normal condition (without magnetic field). An overpotentials of 104 mV and a Tafel slope of 54 mV·dec−1 are attained at 10 mA cm−2 in 1 M KOH under a moderated magnetic field of 100 mT, showing that the external magnetic field taking a positive effect to enhance the kinetic process of the NiCo2S4 nanostructure. The presented results can offer an alternative strategy for further improving the HER property of electrocatalysis by utilizing an external magnetic field.