Scalable Synthesis of NiFe‐LDH/Ni9S8/NF Nanosheets by Two‐Step Corrosion for Efficient Oxygen Electrocatalysis

Abstract Scalable synthesis of non‐noble‐metal‐based electrocatalysts achieved by energy‐saving and cost‐effective strategies towards efficient oxygen evolution is primary significant for the practical application of water splitting, however, it is still a great challenge. In this work, a two‐step corrosion engineering is proposed to construct ultrathin NiFe‐LDH and high‐conductivity Ni 9 S 8 composites (denoted as NiFe‐LDH/Ni 9 S 8 /NF) at room temperature. By ingeniously using the corrosion reaction between nickel foam (NF) and S 2 O 3 2− under acidic condition, Ni 9 S 8 was firstly formed on the surface of Ni foam. Then, ultrathin NiFe‐LDH nanosheets were precipitated on the Ni 9 S 8 surface through an ultrafast Fe 2+ ions‐assisted corrosion treatment. Featured with fast electron/mass transfer rates, sheet‐stacked structure, and superior hydrophilicity, NiFe‐LDH/Ni 9 S 8 /NF exhibits an enhanced oxygen evolution reaction (OER) activity with low overpotentials of 223 and 265 mV at 10 and 100 mA cm −2 , respectively. Such feasible, economical, and scale‐up synthesis method might open a new avenue for the wide‐scale fabrication of materials for various electrochemical applications.