Co 3 O 4 nanoparticles supported on N-doped electrospinning carbon nanofibers as an efficient and bifunctional oxygen electrocatalyst for rechargeable Zn–air batteries

Composite materials made up of non-precious metal oxide and N-doped carbon materials are great potential bifunctional catalysts for Zn–air batteries (ZABs) owing to the synergistic effect caused by the two components. Herein, Co 3 O 4 nanoparticles supported on N-doped electrospun carbon nanofibers (CNFs) with superior bifunctional activity for the ORR/OER and remarkable electrocatalytic stability in an alkaline electrolyte are designed and synthesized. In addition, the hybrid electrocatalyst further promotes the rechargeable ZABs with a low overpotential, high efficiency and prolonged cycling life, superior to those using precious metal catalysts of Pt/C and IrO 2 . Such a remarkable bifunctional catalytic activity is attributed to the enhanced charge transfer capability, abundant exposed catalytically active sites and the synergistic effect among the Co 3 O 4 nanoparticles and CNFs. This work should provide a convenient pathway for the design of non-precious metal and carbon hybrid materials that can be employed as efficient electrocatalysts for large-scale implementations of renewable energy conversion devices.