A covalent hybrid of spinel manganese-cobalt oxide (MnCo₂O₄) and nitrogen-doped reduced graphene oxide (N-rmGO) was developed as an efficient oxygen reduction reaction (ORR) electrocatalyst in alkaline conditions. The hybrid was synthesized by directly nucleating and growing MnCo₂O₄ nanoparticles on N-doped reduced graphene oxide, resulting in strong covalent coupling between the spinel oxide and the graphene. This coupling enhanced the catalytic activity and stability of the hybrid compared to physical mixtures of nanoparticles and carbon materials. XANES analysis confirmed the formation of covalent bonds between the spinel oxide and N-doped graphene, with Mn³⁺ substitution in the spinel structure increasing catalytic activity. The hybrid exhibited higher ORR activity and stability than Pt/C, with a current density of 151 mA/cm² at 0.7 V vs. RHE, surpassing Pt/C at higher overpotentials. The hybrid also showed excellent stability, with only a 3.5% decrease in current density after 20,000 seconds of operation. The covalent coupling enhanced electron transport between the spinel oxide and graphene, improving catalytic performance. The hybrid demonstrated a four-electron reduction pathway for ORR, with an electron transfer number of ~3.9. The hybrid also showed high activity in 0.1 M KOH and was effective for both ORR and OER. The study highlights the importance of covalent coupling and Mn substitution in enhancing the performance of spinel oxide-based catalysts for energy applications.A covalent hybrid of spinel manganese-cobalt oxide (MnCo₂O₄) and nitrogen-doped reduced graphene oxide (N-rmGO) was developed as an efficient oxygen reduction reaction (ORR) electrocatalyst in alkaline conditions. The hybrid was synthesized by directly nucleating and growing MnCo₂O₄ nanoparticles on N-doped reduced graphene oxide, resulting in strong covalent coupling between the spinel oxide and the graphene. This coupling enhanced the catalytic activity and stability of the hybrid compared to physical mixtures of nanoparticles and carbon materials. XANES analysis confirmed the formation of covalent bonds between the spinel oxide and N-doped graphene, with Mn³⁺ substitution in the spinel structure increasing catalytic activity. The hybrid exhibited higher ORR activity and stability than Pt/C, with a current density of 151 mA/cm² at 0.7 V vs. RHE, surpassing Pt/C at higher overpotentials. The hybrid also showed excellent stability, with only a 3.5% decrease in current density after 20,000 seconds of operation. The covalent coupling enhanced electron transport between the spinel oxide and graphene, improving catalytic performance. The hybrid demonstrated a four-electron reduction pathway for ORR, with an electron transfer number of ~3.9. The hybrid also showed high activity in 0.1 M KOH and was effective for both ORR and OER. The study highlights the importance of covalent coupling and Mn substitution in enhancing the performance of spinel oxide-based catalysts for energy applications.