NiS/CeO۲ and CoS/CeO۲ Nanocomposites as Novel Electrocatalysts for the Oxygen Evolution Reaction

Oxygen evolution reaction is the anodic half-reaction of water splitting, which usually controls the overall rate due to its complex mechanism and sluggish kinetics. In this work, we present the synthesis and characterization of NiS/CeO۲ and CoS/CeO۲ nanocomposites as novel electrocatalysts for the oxygen evolution reaction in an alkaline solution. These nanocomposites were prepared via a combination of hydrothermal synthesis and calcination in ambient air. SEM and elemental mapping revealed that the as-synthesized nanocomposites consist of CeO۲ nanorods uniformly covered with NiS (CoS) nanoparticles. The NiS/CeO۲ and CoS/CeO۲ exhibited overpotentials of ۳۵۷ and ۴۴۲ mV (at a current density of ۱۰ mA/cm۲) and Tafel slopes of ۶۴ and ۱۵۸ mV/decade in ۱.۰ M KOH, respectively.

کلیدواژه ها:

Water splitting ، Oxygen evolution reaction ، Electrocatalyst ، Nanocomposite