Expediting Corrosion Engineering for Sulfur-Doped, Self-Supporting Ni-Fe Layered Dihydroxide in Efficient Aqueous Oxygen Evolution

Abstract

Electrochemical water-splitting is widely acknowledged as a renewable strategy for hydrogen production, but it is primarily constrained by the sluggish reaction kinetics of the anode oxygen evolution reaction (OER). In our study, we employ a fast room-temperature corrosion engineering strategy for the construction of a sulfur-doped Ni-Fe layered dihydroxide catalyst (S-NiFe LDH). With the assistance of a sulfur source, microsphere morphology with an ultra-thin lamellar surface cross-arrangement can be rapidly grown on the surface of an iron foam substrate, ensuring a substantial electrochemical interface. The composition of Ni species in the catalysts can be regulated by simply adjusting the amount of Ni2+ and reaction time. Functioning as an OER catalyst, the S-NiFe LDH demonstrates high activity and reaction kinetics, featuring a minimal overpotential of 120.0 mV to deliver a current density of 10 mA cm−2, a small Tafel slope of 39.5 mV dec−1 and a notable electrical double-layer capacitance (Cdl) of 31.3 mF cm−2. The remarkable electrocatalytic performance can be attributed to its distinctive three-dimensional (3D) structure and sulfur dopants, which effectively regulate the electrochemical interface and electronic structure of NiFe LDH. This work provides valuable insights for expeditious materials design.