Zinc-assisted synthesis of Fe-N-C catalysts based on polyaniline with high oxygen reduction reaction catalytic activities in direct methanol fuel cells

Fe-N-C catalysts show great potential to replace Pt/C in oxygen reduction reaction (ORR). Polyaniline (PANI) is an ideal precursor with an abundant and homogeneous distribution of nitrogen sources. However, Fe-N-C based on PANI suffers from an unsatisfied performance in acidic media. Herein, a facile zinc-assisted synthesis of Fe-N-C based on PANI was reported in this paper. ZnCl2 templates can be removed completely in the pyrolysis procedure, creating abundant porous structures to accelerate the mass transfer and boost ORR performance. Fe-N-C-2 with the adequate and optimizing amount of zinc shows an excellent ORR performance (E-1/2 = 0.91 V in alkaline and E-1/2 = 0.825 V in acidic media) compared with Pt/C (E-1/2 = 0.89 V in alkaline and E-1/2 = 0.84 V in acidic media). Furthermore, a high power density and a long-term operation within 6 h of direct methanol fuel cell based on brilliant Fe-N-C-2 verify a great promising application of potable power devices in the future.