Highly efficient and active Co-N-C catalysts for oxygen reduction and Zn-air batteries

In this study, the Lewis doping approach of polyaniline (PANI) was employed to fabricate cobait-nitrogen-carbon (Co-N-C) oxygen electrocatalysts for Zn-air batteries, aiming to enhance the active spots of Co-N-C. This resulting Co-N-C catalysts exhibited well-defined nanofiber networks, and the Brunauer-Emmett-Teller (BET) analysis confirmed their substantial specific surface area. Electrochemical experiments demonstrated that the Co-N-C catalysts achieved the half-wave potential (vs. RHE) of 0.85 V in alkaline medium, overcoming Pt/C and iron-nitrogen-carbon (Fe-N-C) counterparts in extended cycle testing with only a 25 mV change in a half-wave potential after 5000 cycles. Remarkably, the highest power density measured in the zinc (Zn)-air battery reached 227 mW/cm2, a significant improvement over the performance of 101 mW/cm2 of the platinum on activated carbon (Pt/C) catalyst. These findings highlight the advantageous stability enhancement associated with the utilization of Co in the Co-N-C catalysts.