Unravelling the Role of Metallic Cu in Cu-CuFe₂O₄/C Nanohybrid for Enhanced Oxygen Reduction Electrocatalysis

Interface engineering of metal and semiconductive spinel oxides is an efficient approach to improve conductivity and ultimately boosting electrocatalytic property. Herein, we present the synthesis of Cu-CuFe2O4 nanohybrid coupled with conductive carbon (Cu-CuFe2O4/C) as a highly efficient electrocatalyst for oxygen reduction reaction (ORR). The metallic Cu and semiconductive oxide CuFe2O4 interface provides better electronic conductivity, and carbon matrix offers conductive support for electron/ion transfer process. Consequently, the Cu-CuFe2O4/C electrode exhibits superior current density (4.35 mA cm–2) in comparison to the standard Pt/C (3.81 mA cm–2) along with other catalyst systems toward ORR. Thus, the nanohybrid that combines the advantages of metallic Cu and chemical interaction of carbon matrix along with its magnetic behavior establishes remarkable enhancement in ORR activity. Furthermore, it also exhibits superior mechanical and electrochemical stability compared to that of Pt/C. Thus, the unique structural design offers a new approach for the fabrication of magnetic metal-oxides electrodes with enhanced ORR performance via interface engineering.