Ternary single metal atom oxides anchored on bimetal oxides for enhanced electrocatalytic oxygen evolution reaction in alkaline medium

Abstract

A stronger electrocatalytic oxygen evolution reaction (OER) may be achieved by anchoring W, Cu, and Co single metal atom oxides (SMAO) nanocomposite catalysts with Co₃O₄-CeO₂ coupled rGO (R-Co₃O₄-CeO₂-WCC-3). The as-obtained catalyst materials are subjected to studies employing powder XRD, XPS, FESEM, HRTEM, and STEM-HAADF to assess the material’s structural purity, oxidation state of components, surface morphology, and presence of SMAO. The SMAO anchoring by a highly scalable one-step sonication synthesis significantly enhanced the catalysts’ mass, charge transfer, and active site density. Excellent catalytic activity for OER under alkaline circumstances was accordingly shown by the R-Co₃O₄-CeO₂-WCC electrocatalysts. Particularly, the optimal R-Co₃O₄-CeO₂-WCC-3 catalyst had a relatively small Tafel slope of 52 mV dec^–1 and low overpotentials of 282 and 353 mV for current densities of 10 and 100 mA cm⁻² respectively. Additionally, we used the DFT calculation to examine the OER activity of a single W atom anchoring on the CO₃O₄-CeO₂ materials. All of these results suggest that Co₃O₄-CeO₂-rGO could be used as an anchor for transition single metal atom catalysts to make new, interesting, and useful electrocatalysts.