Quenching induced Cu and F co-doping multi-dimensional Co₃O₄ with modulated electronic structures and rich oxygen...

The development of highly efficient non-precious electrocatalysts for the oxygen evolution reaction (OER) remains a significant challenge. In this work, we introduce a highly effective OER electrocatalyst, Cu-F-Co₃O₄, synthesized by doping copper (Cu) and fluorine (F) into Co₃O₄ using a quenching method. Both experimental and theoretical calculations reveal that Cu and F incorporation significantly shifts the d-band center closer to the Fermi level, creates abundant oxygen vacancies, and facilitates the reconstruction of the catalyst to form the CuCo₂O_4-yF_y/CuO heterojunction. This structural modification enhances the OER performance of the catalyst. Additionally, the multi-dimensional architecture exposes more active sites and accelerates mass and charge transfer kinetics. The optimal catalyst, Cu-F-Co₃O₄-0.7, demonstrates a low overpotential of 290 mV at 10 mA·cm^-2, along with remarkable stability exceeding 100 h, significantly outperforming both pristine Co₃O₄ and benchmark RuO₂ electrocatalysts. These findings offer new insights into activating surface reconstruction in spinel oxides by engineering both anion and cation defects for water oxidation.