Defect-rich Fe-doped Co3O4 derived from bimetallic-organic framework as an enhanced electrocatalyst for oxygen evolution reaction

Herein, oxygen-deficient Fe-doped Co3O4 polyhedral nanoparticles derived from FeCo‐based bimetal–organic frameworks are prepared for the electrocatalytic oxygen evolution reaction (OER) via a facile self‐templating strategy. A well-defined rhombic dodecahedral structure with abundant oxygen vacancies was constructed based on the coprecipitation, carbonization, oxidation, and partial reduction process. The proposed synthetic method is effective for fabricating a bimetallic hierarchical structure with a rough surface and a moderately controlled electronic structure, which significantly facilitates charge and mass transfer and appropriately exposes the active sites for efficient electrocatalysis. Subsequently, the as-obtained defect-rich Fe-doped Co3O4 nanoparticles was found to be a superior OER electrocatalyst, with a small overpotential of 318 mV required for a current density of 10 mA cm−2, a low Tafel slope of 76.8 mV dec−1, a turnover frequency of 0.1553 s−1 at an overpotential of 370 mV, and outstanding long-term durability in 1.0 M KOH. The proposed strategy will offer a new approach in the design and development of electrochemically active non-noble materials as advanced catalysts for various energy storage and conversion applications.