Engineering VN/Co_5.47N Nanostructures with Interfacial Electronic and Atomic Reorganization for Oxygen Reduction and Zn–Air Batteries

Interfacial electronic and atomic structural reorganization in heterojunction hybrids will unlock great potential for achieving efficient catalysis. Herein, VN/Co5.47N nanopolyhedrons were first prepared by ammonization of functional ZIF-67 with vanadate and further employed as model catalysts to highlight the interfacial electronic and atomic synergistic effects on the oxygen reduction reaction (ORR). X-ray photoelectron spectroscopy confirms the charge transfer from Co5.47N to VN, which can further regulate the intrinsic electronic structure and accelerate the ORR catalytic kinetics of VN/Co5.47N. Meanwhile, X-ray diffraction in combination with transmission electron microscopy discloses abundant atomic defects in the VN/Co5.47N coupling interface, and such interfacial disordered atoms and/or dangling bonds act as extra active sites for effective ORR catalysis. Benefiting from the interfacial electronic and atomic advantages, the as-prepared VN/Co5.47N realizes an ultralow half-wave potential of 0.81 V, high selectivity, and favorable stability. More importantly, the outstanding ORR performances of VN/Co5.47N endow the homemade Zn–air battery with VN/Co5.47N as an air cathode to afford outstanding performances in specific discharge capacity, power density, and discharge–charge cycle stability. This work paves the way for insight into the atomic interface–performance relationship in ORR, and meanwhile, these findings can be extended to design other active catalysts.