One-dimensional multilevel stalactite-like Ni3S2-Fe(Mo2S4) bifunctional electrocatalyst with excellent oxygen evolution reaction and overall water splitting performance

Sluggish multi-electron transfer process of the oxygen evolution reaction (OER) hinders the further advancement of electrolysis for hydrogen production. Here, a one-dimensional multilevel stalactite-like Ni3S2-Fe(Mo2S4) with excellent oxygen evolution performance was successfully synthesized using a universal two-step hydrothermal method. The nanorod arrays increase the active area and promote electron transfer. In addition, the synergistic effect between the two transition metal sulfides further enhances the internal kinetics of the catalyst to improve the overall water splitting performance. This heterostructure can achieve a current density of 10 mA cm(-2) with the low overpotential of only 166 mV (OER) and 177 mV (HER). As a bifunctional catalyst, it also can achieve the overall water splitting process at a low voltage of 1.573 V and demonstrates good stability over a continuous period of 48 h.