NiCoMo Hydroxide Nanosheet Arrays Synthesized via Chloride Corrosion for Overall Water Splitting

Designing nonprecious electrocatalysts with multiple active sites and prolonged durability in an integrated electrolyte toward water splitting is momentous for renewable energies being reserved in chemical fuels. Herein, we developed a method for synthesizing multimetallic hydroxide nanosheets by corroding nickel foam with chloride ions, which enabled the screening and discovery of various multimetallic hydroxide electrocatalysts toward oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). We discovered that Ni5Co3Mo–OH nanosheets exhibited electrocatalytic performances toward OER (η100 = 304 mV) and HER (η10 = 52 mV). Moreover, Ni5Co3Mo–OH can be employed as active bifunctional catalysts toward overall water splitting with a low cell voltage of 1.43 V at 10 mA·cm–2 (1.60 V at 100 mA·cm–2) and stable operation for 100 h (100 mA·cm–2). This work provides a method to develop multimetallic hydroxides for electrocatalysis and energy conversion.