Fe, Co, N-functionalized carbon nanotubes in situ grown on 3D porous N-doped carbon foams as a noble metal-free catalyst for oxygen reduction†
Abstract
Designing and manipulating advanced oxygen reduction reaction (ORR) electrocatalysts are of critical importance for the widespread application of fuel cells. In this work, we report a highly versatile and one-pot pyrolysis route for the mass production of a novel three-dimensional N, Fe, Co-functionalized carbon nanotubes rigidly grown on N-doped carbon foams (3D FeCoN–CNTs/NCFs) serving as a noble-metal free catalyst for the oxygen reduction reaction (ORR). Different from the previously reported carbon materials, in the present 3D porous structure, the N, Fe, Co-doped carbon nanotubes are rigidly grown on the skeleton of 3D nitrogen-doped carbon foams (NCFs), showing a high electrochemical stability. Moreover, due to the synergistic effect of the Fe/Co and the N species with the formation of Fe/Co–Nx complexes in the 3D hybrid carbon material and the multiple active sites on the porous structure, the 3D hybrid displayed superior catalytic performance for ORR, high operation stability and strong methanol/CO crossover resistance in alkaline medium. The stable porous structure and the excellent catalytic performance make the 3D FeCoN–CNTs/NCFs a promising non-precious-metal cathodic electrocatalyst for fuel cells.