Fe3C@nitrogen doped CNT arrays aligned on nitrogen functionalized carbon nanofibers as highly efficient catalysts for the oxygen evolution reaction

Abstract

Fe₃C based catalysts are found to be one of the most promising electrocatalysts for the oxygen evolution reaction (OER). Herein, we report on a nanoarchitectured material composed of Fe₃C nanoparticles encapsulated at the tip of nitrogen-enriched carbon nanotubes (NCNTs), which are aligned on one dimensional (1D) nitrogen-doped carbon nanofibers (Fe₃C@NCNTs-NCNFs) by a scalable electrospinning technique, as a high performance OER catalyst. The unique 3D hierarchical architecture of Fe₃C@NCNTs-NCNFs leads to highly exposed active sites, enhanced electron transfer properties and strong synergistic coupled effects. Fe₃C@NCNTs-NCNFs exhibit an outstanding catalytic performance with a high current density (10 mA cm⁻² at an overpotential of 284 mV), a low Tafel slope (56 mV dec⁻¹), a low charge transfer resistance and strong durability in 1 M KOH solution. The electrochemical evaluation demonstrates that the Fe₃C@NCNTs-NCNF composite is a promising electrocatalyst for the OER in alkaline solution.