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

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 Ni9S8 composites (denoted as NiFe-LDH/Ni9S8/NF) at room temperature. By ingeniously using the corrosion reaction between nickel foam (NF) and S2O32- under acidic condition, Ni9S8 was firstly formed on the surface of Ni foam. Then, ultrathin NiFe-LDH nanosheets were precipitated on the Ni9S8 surface through an ultrafast Fe2+ ions-assisted corrosion treatment. Featured with fast electron/mass transfer rates, sheet-stacked structure, and superior hydrophilicity, NiFe-LDH/Ni9S8/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.

Automated summary

A two-step corrosion engineering method was proposed to synthesize ultrathin NiFe-LDH and high-conductivity Ni9S8 composites for efficient oxygen evolution. The resulting composite exhibited enhanced OER activity with low overpotentials, showing potential for wide-scale fabrication of materials for various electrochemical applications.