Hedgehog-like NiMoSe microsphere arrays for efficient overall water splitting

Abstract

We report a one-step hydrothermal method to synthesize hedgehog-like NiMoSe microsphere arrays on nickel foam (NiMoSe/NF), the morphology of which is determined by tuning the content of Ni2+ in the growth solution because Ni2+ can promote the growth of rod-like structure. Owning to the unique hedgehog-like microsphere structure composed of microrod arrays, NiMoSe/NF possesses a large catalytic active area for uploading more active sites, and is beneficial to electron transfer and gas precipitation during catalytic reactions. The synthesized NiMoSe/NF only requires an overpotential of 88 mV/190 mV to achieve a current density of 10 mA cm−2 with stability of 44 h/62 h for the hydrogen evolution reaction (HER)/oxygen evolution reaction (OER). When NiMoSe/NF is used as both the cathode and anode, the system can afford 10 mA cm−2 current density at low battery voltage of 1.50 V with a stability of 48 h. The work promotes the development of transition metal electrocatalysts for high-efficient splitting of water.