Nano-Co-embedded carbon nanofibers for oxygen reduction reaction in Zn-air batteries

The preparation of inexpensive, environmentally friendly, and stable electro-catalysts is crucial for realizing large-scale practical applications of Zn-air batteries. Herein, Co nanoparticles are successfully encapsulated in N-doped carbon nanofibers by electrospinning technique. The obtained material has the characteristics of stable fibrous structure, abundant active centers and fast electron transport. As expected, Co@HPCNFs-800 exhibits high catalytic activity with its initial potential (0.925 V) and onset half-wave potential (0.824 V). Meanwhile, the stability of Co@HPCNFs-800 is significantly higher than commercial Pt/C. Most importantly, the rechargeable Zn-air batteries using Co@HPCNFs-800 catalyst exhibit good open-circuit voltage and cycling stability, demonstrating their potential for practical application. Therefore, this facile method can generally be used to synthesize non-noble metal electrocatalysts to improve energy conversion efficiency.