The intriguing ORR performance of iron and nitrogen co-doped biomass carbon composites incorporating surface-modified polyaniline-derived carbon

As a clean energy conversion device, fuel cell can greatly alleviate the environmental pollution problem. Developing cost-effective oxygen reduction reaction (ORR) catalysts with high performance is of great significance to improve the efficiency of fuel cells and promote its large-scale use. Here, we successfully fabricated an iron and nitrogen co-doped carbon–carbon composite (Fe-N-C B350 -900Z@C PANI ) by modifying a pre-synthesized iron and nitrogen co-doped biomass carbon (Fe-N-C B350 -900Z) with polyaniline derived carbon (C PANI ). The obtained Fe-N-C B350 -900Z@C PANI displays excellent ORR catalytic activity, as reflected by the positive onset potential of 0.13 V vs Hg/HgO and high limiting current density of 5.92 mA cm −2 , which significantly outperforms the benchmark Pt/C (0.07 V and 4.70 mA cm −2 , respectively). Meanwhile, it also presents remarkable catalytic stability and the great methanol tolerance. The excellent catalytic performance of Fe-N-C B350 -900Z@C PANI is attributed to the merits of the hierarchical porous structure and large specific surface area up to 955 m 2 g −1 formed by synergism of C B and C PANI , which effectively promotes the mass transfer and accessibility of active sites.