The synthesis of Fe/N–C@CNFs and its electrochemical performance toward oxygen reduction reaction

Abstract

The one-dimensional filamentous carbon nanofibers hold great promise to substitute noble catalysts ascribing to the excellent physicochemical properties, environmentally friendly, easy to prepare, etc. Synthesizing non-noble catalysts with outstanding electro-catalytic activity for oxygen reduction reaction and excellent durability and application in the field of commercialization still exist lots of challenges. Herein, we report a facile synthesis of carbon nanofibers coated with iron doping nitrogen-carbon (Fe/N–C@CNFs) derived from carbon nanofibers coated with polyaniline (PANI@CNFs) via chemical vapor deposition and heat-treatment, which exhibit an outstanding catalytic activity toward oxygen reduction reaction. In detail, the Fe/N–C@CNFs exhibit onset potential of 0.99 V (vs RHE) and half-wave potential of 0.80 V (vs RHE) in 0.1 M KOH solution, indicating superior electrochemical activity for oxygen reduction reaction (ORR). Meantime, the transferred electron number of oxygen reduction reaction was 3.77, suggesting a nearly 4e− transferring process with little intermediate product (H2O2). Moreover, the relative current value of carbon nanofibers coated with nitrogen-carbon film (N–C@CNFs) and Fe/N–C@CNFs maintain 89.6% and 88.2% respectively after 40,000 s, exhibiting good stability and durability. This facile and easy method could provide inspiration for synthesizing carbon nanofibers-based (CNFs-based) oxygen reduction reaction catalysts with excellent catalytic activity and good stability.