Increased charge and mass transfer derived-sheet-like Fe0.67Ni0.33OOH-Fe2O3@NF array for robust oxygen evolution reaction

Abstract The sluggish kinetics of oxygen evolution reaction (OER) still remains a primary obstacle to hydrogen production via water electrolysis. The evolution of exceptionally active and durable non-noble-metal-based OER electrocatalyst as a prerequisite for practical applications is significant. In this paper, we report a facile one-pot hydrothermal method for synthesizing a porous Fe0.67Ni0.33OOH-Fe2O3@NF sheet-like nanoarray as an OER electrocatalyst. As expected, this Fe0.67Ni0.33OOH-Fe2O3@NF electrocatalyst exhibits desirable OER performance with low overpotential (232 mV) at 10 mA cm−2 current density, 34 mV dec−1 Tafel slope, impressive durability over 1000 CV cycles, and 110 h continuous i-t response at 30 mA cm−2 current density. These values exceed those observed from most reported non-/noble-metal-based OER electrocatalysts to date, and these observations are consistent with exposure of numerous intrinsically active sites, synergistic modulation of charge transfer, and intense interactions between Fe, Ni, and O, as well as increased mass transfer based on separation of bubbles generated on the integrated electrode surface. These results illustrate the potential for this strategy to provide a low-cost, highly-active OER electrocatalyst as a kind of renewable energy storage devices, such as metal-air battery and water oxidation.