LAUSR

Abstract The development of efficient active inexpensive metal catalysts for water electrolysis has been a promising way to produce hydrogen. Herein, an electrode composed of NiCo2O4 nanoneedle and molybdenum carbide coated on carbon cloth (NiCo2O4/Mo2C/CC) is prepared based on the hydrothermal process. The CC enhances the electric conduction ability of the system. The heterojunction between Mo2C and NiCo2O4 makes NiCo2O4 nanoneedle diminished and leads to production of richened oxygen vacancies. Therefore, NiCo2O4/Mo2C/CC presents the low overpotential of 120 mV for hydrogen evolution reaction (HER) and 220 mV for oxygen evolution reaction (OER) at 10 mA cm−2 used in water splitting. Meanwhile, NiCo2O4/Mo2C/CC shows remarkable oxygen reduction reaction (ORR) performance. With NiCo2O4/Mo2C/CC used as catalyst in air cathode, the prepared Zn-air battery exhibits a capacity of 778 mAh g−1 and an energy density of 104 mW cm−2, showing promising applications to replace the expensive rare-metal catalysts.