Fe, N codoped porous carbon nanosheets for efficient oxygen reduction reaction in alkaline and acidic media

Abstract

Electrospinning typically employed to fabricate nanofibers was first used to prepare Fe and N doped porous carbon nanosheets (Fe–N/CNs) as oxygen reduction reaction (ORR) electrocatalysts. Polyacrylonitrile nanofibers containing a small amount of ferrocenes (Fer-PAN) were produced by electrospinning. When Fer-PAN was preoxidized at 300 °C in the air (Fer-PAN-300), nanosheets were formed and occupied the interspace between nanofibers. Fe–N/CNs was finally obtained using carbonized Fer-PAN-300 at 900 °C in N2. The Fe–N/CNs incorporated the advantages of carbon nanofiber webs and porous nanocarbon materials, inclusive of comparatively high conductivity and large specific surface area. In both alkaline and acidic electrolyte, the Fe–N/CNs took on similar even better ORR catalytic activity than other catalysts reported elsewhere, and better stability than those of commercial Pt/C.