Co3O4–C@FeMoP on nickel foam as bifunctional electrocatalytic electrode for high-performance alkaline water splitting.

Exploring low-cost, highly efficient, and sustainable non-precious electrocatalysts for electrolytic H 2 generation is driving research for the sustainable green urban development. Herein, we present a simple synthetic approach, through a two-step process, to prepare the bifunctional electrode of Co 3 O 4 –C@FeMoP hybrid micro rods/nanosheets anchored on nickel foam (NF), in which the Co 3 O 4 –C microrods grown on NF surface are decorated by FeMoP nanosheet layers, which is directly grown through a simple hydrothermal followed by post-phosphorization processes. The obtained hybrid hierarchical Co 3 O 4 –C@FeMoP/NF shows a significant enhancement in the electrocatalytic activities of oxygen/hydrogen evolution reactions (OER/HER) in comparison to the individual Co 3 O 4 –C and FeMoP nanostructures, thanks to more heterointerface active sites provided by FeMoP nanostructures with three-dimensional (3-D) layered architectures. The Co 3 O 4 –C@FeMoP/NF catalyst exhibits a relatively small overpotential of 200 mV vs. RHE for OER to achieve 20 mA/cm2 and 123 mV vs RHE at 10 mA/cm2 for HER along with excellent durability in alkaline electrolytes. We demonstrate the bifunctional electrocatalytic electrode as the electrolyzer for the generation of H 2 via water splitting at small applied voltage of 1.61 V to achieve 10 mA/cm2 and good stability for 24-h continuous running. • Synthesis of high-activity catalyst material Co 3 O 4 –C@FeMoP/NF. • Decent electrocatalytic activity toward OER and HER in alkali. • Alkaline water electrolysis system with bifunctional electrocatalyst electrode. [ABSTRACT FROM AUTHOR]