The synthesis of electrospun N-doped carbon nanofibers with embedded Fe2N/Fe3C species for catalyzing the O2 and CO2 reduction reactions

The need for bi-functional catalysts that facilitate both the oxygen reduction (ORR) and carbon dioxide reduction (CO 2 RR) reactions arises from their potential to help solve the critical problems of carbon neutrality and renewable energy conversion. However, there are few reports on the development of bi-functional catalysts for zinc-air battery-driven CO 2 RR devices. We introduce a novel approach for synthesizing Fe 2 N/Fe 3 C species embedded in nitrogen-doped carbon nanofibers by electrospinning a solution of Hemin and polyacrylonitrile in N,N-dimethylformamide. The material has an exceptional catalytic performance, with a half-wave potential of 0.91 V versus RHE for the ORR and values of over 90% for both the selectivity and Faradaic efficiency for the CO 2 RR. The high catalytic performances are attributed to the strong coupling between the Fe 3 C/Fe 2 N heterostructure and the Fe-N-C sites in the nitrogen-doped carbon nanofibers. Notably, both Fe 3 C and Fe 2 N play distinct roles in both the ORR and CO 2 RR. This investigation indicates a way for designing advanced carbon-based bi-functional catalysts for use in this field. Download: Download high-res image (61KB) Download: Download full-size image