On an easy way to prepare highly efficient Fe/N-co-doped carbon nanotube/nanoparticle composite for oxygen reduction reaction in Al–air batteries

Developing an efficient and low-cost oxygen reduction reaction (ORR) catalyst is the key to realize the commercialization of metal–air batteries. Fe/N-co-doped carbon materials (Fe–N–C) are regarded as one of the most promising oxygen reduction reaction (ORR) catalysts to replace expensive and unstable Pt/C in metal–air batteries. In this work, a new kind of Fe/N-co-doped special carbon nanotube/nanoparticle hybrid catalyst was obtained by using cheap precursors, i.e., ketjenblack EC-600JD (KB), melamine and iron nitrate via a facile high-temperature pyrolysis treatment. The catalyst shows a comparative oxygen reduction reaction (ORR) catalytic activity and better stability than commercial 20 wt% Pt/C in the same test conditions. The outstanding performance results from the doping of Fe and N, which could effectively increase the active sites. Furthermore, a special bamboo-like carbon nanotube is generated due to the catalysis of Fe source. The catalyst exhibits good performance in Al–air batteries. The maximum power density can reach to 300 mW cm⁻² with the cell voltage of about 1 V and the current density of 300 mA cm⁻².