Amorphous Mo-doped NiS Se Nanosheets@Crystalline NiS Se Nanorods for High Current-density Electrocatalytic Water Splitting in Neutral Media.

It is vitally important to develop highly active, robust and low-cost transition metal-based electrocatalysts for overall water splitting in neutral solution especially at large current density. In this work, amorphous Mo-doped NiS Se nanosheets@crystalline NiS Se nanorods (Am-Mo-NiS Se ) was synthesized using a facil one-step strategy. In phosphate buffer saline solution, the Am-Mo-NiS Se shows tiny overpotentials of 48 and 209 mV for hydrogen evolution reaction (HER), 238 and 514 mV for oxygen evolution reaction (OER) at 10 and 1000 mA cm , respectively. Moreover, Am-Mo-NiS Se delivers excellent stability for at least 300 h without obvious degradation. Theoretical calculations revealed that the Ni sites in the defect-rich amorphous structure of Am-Mo-NiS Se owns higher electron state density and strengthened the binding energy of H O, which will optimize H adsorption/desorption energy barriers and reduce the adsorption energy of OER determining step.