Ni-NiO Heterojunction: A Binder-Free Catalyst for Enhanced Oxygen Evolution Reaction.

ABSTRACT: In this study, we applied a two-step electrochemical anodization process to produce highly porous nanostructured nickel suboxides. We then annealed these materials in different environments: air, Ar, and Ar/H₂. Annealing in a reductive environment (Ar/H₂) resulted in a Ni-NiO heterojunction with a high defect density, as confirmed by the Mott-Schottky analysis. Our results demonstrate that these defects and active sites significantly enhance the electrocatalytic activity for the oxygen evolution reaction (OER). Utilizing X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HR-TEM), and electrochemical analysis, we demonstrate that the heterojunction system containing Ni-NiO, for

SUBMITTER: Farahbakhsh N 

PROVIDER: S-EPMC12423888 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature