Iron-doped nickel disulfide nanoarray: A highly efficient and stable electrocatalyst for water splitting

Developing efficient water-splitting electrocatalysts, particularly for the anodic oxygen evolution reaction (OER), is an important challenge in energy conversion technologies. In this study, we report the development of iron-doped nickel disulfide nanoarray on Ti mesh (Fe0.1-NiS2 NA/Ti) via the sulfidation of its nickel–iron-layered double hydroxide precursor (NiFe-LDH NA/Ti). As a three-dimensional OER anode, Fe0.1-NiS2 NA/Ti exhibits remarkable activity and stability in 1.0 M KOH, with the requirement of a low overpotential of 231 mV to achieve 100 mA·cm−2. In addition, it exhibits excellent activity and durability in 30 wt.% KOH. Notably, this electrode is also efficient for the cathodic hydrogen evolution reaction under alkaline conditions.