Affiliation:
1. MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage School of Chemistry and Chemical Engineering Harbin Institute of Technology Harbin 150001 P. R. China
2. Key Laboratory for Photonic and Electronic Bandgap Materials Harbin Normal University Harbin 150025 P. R. China
3. National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of Technology Harbin 150001 P. R. China
Abstract
AbstractConstruction of heterojunctions is an effective strategy to enhanced electrocatalytic oxygen evolution reaction (OER), but the structural evolution of the active phases and synergistic mechanism still lack in‐depth understanding. Here, an FeOOH/Ni3S2 heterostructure supported on nickel foam (NF) through a two‐step hydrothermal‐chemical etching method is reported. In situ Raman spectroscopy study of the surface reconstruction behaviors of FeOOH/Ni3S2/NF indicates that Ni3S2 can be rapidly converted to NiOOH, accompanied by the phase transition from α‐FeOOH to β‐FeOOH during the OER process. Importantly, a deep analysis of Ni─O bond reveals that the phase transition of FeOOH can regulate the lattice disorder of NiOOH for improved catalytic activity. Density functional theory (DFT) calculations further confirm that NiOOH/FeOOH heterostructure possess strengthened adsorption for O‐containing intermediates, as well as lower energy barrier toward the OER. As a result, FeOOH/Ni3S2/NF exhibits promising OER activity and stability in alkaline conditions, requiring an overpotential of 268 mV @ 100 mA cm−2 and long‐term stability over 200 h at a current density of 200 mA cm−2. This work provides a new perspective for understanding the synergistic mechanism of heterogeneous electrocatalysts during the OER process.
Funder
National Natural Science Foundation of China
Subject
Biomaterials,Biotechnology,General Materials Science,General Chemistry