Interfacial electronic modulation in CoWO4/Co3O4 heterostructures for efficient oxygen evolution reaction
Journal
International Journal of Hydrogen Energy
Date Issued
2026-08
Author(s)
Thiyagarajan, Dhandayuthapani
University of Atacama
Lee, Bong-Kee
Abstract
Cobalt oxide-based electrocatalysts have attracted considerable attention for alkaline oxygen evolution reaction (OER) owing to their earth abundance and favorable redox properties; however, their practical application is limited by sluggish reaction kinetics and structural instability during prolonged operation. Herein, CoWO4/ Co3O4/CC heterostructure nanorod heterostructures were directly grown on carbon cloth through a sodium tungstate-assisted conversion strategy followed by thermal treatment. Post-OER analyses revealed stable cobalt surface electronic features together with increased defect-related oxygen species, indicating dynamic surface reconstruction during electrocatalytic operation. High-resolution transmission electron microscopy demonstrated amorphization of the outer CoWO4 layer while preserving the crystalline Co3O4 framework. Density functional theory calculations revealed enhanced Co-O-W orbital interactions and improved adsorption energetics for oxygen intermediates. Benefiting from synergistic interfacial interactions and improved charge-transfer behavior, the CoWO4/Co3O4/CC heterostructure achieved a low overpotential of 210 mV at 10 mA cm- 2 with stable operation for approximately 80 h in alkaline electrolyte.


