Developing an efficient and durable oxygen reduction electrocatalyst is critical for clean-energy technology,such as fuel cells and metal-air batteries.In this study,we developed a facile strategy for the preparation of flexible,porous,and well-dispersed metal-heteroatom-doped carbon nanofibers by direct carbonization of electrospun Zn/Co-ZIFs/PAN nanofibers (Zn/Co-ZIFs/PAN).The obtained Zn/Co and N co-doped porous carbon nanofibers carbonized at 800 ℃ (Zn/Co-N@PCNFs-800) presented a good flexibility,a continuous porous structure,and a superior oxygen reduction reaction (ORR) catalytic activity to that of commercial 20 wt％ Pt/C,in terms of its onset potential (0.98 V vs.RHE),half-wave potential (0.89 V vs.RHE),and limiting current density (-5.26 mA cm-2).In addition,we tested the suitability and durability of Zn/Co-N@PCNFs-800 as the oxygen cathode for a rechargeable Zn-air battery.The prepared Zn-air batteries exhibited a higher power density (83.5 mW cm-2),a higher specific capacity (640.3 mAh g-1),an excellent reversibility,and a better cycling life than the commercial 20 wt％ Pt/C + RuO2 catalysts.This design strategy of flexible porous non-precious metal-doped ORR electrocatalysts obtained from electrospun ZIFs/polymer nanofibers could be extended to fabricate other novel,stable,and easy-to-use multi-functional electrocatalysts for clean-energy technology.