No abstract

No abstract

No abstract

Graphene aerogel‐supported manganese ferrite (Mn x Fe 3−x O 4 /GAs) and reduced‐graphene oxide/manganese ferrite composite (MnFe 2 O 4 /rGO) were synthesized and studied as cathode catalysts for oxygen reduction reactions in urea/O 2 fuel cells. MnFe 2 O 4 /GAs exhibited a 3D framework with a continuous macroporous structure. Among the investigated Fe/Mn ratios, the more positive oxygen reduction onset potential was observed with Fe/Mn=2/1. The half‐wave potential of MnFe 2 O 4 /GAs was considerably more positive than that of MnFe 2 O 4 /rGO and comparable with that of Pt/C, while the stability of MnFe 2 O 4 /GAs significantly higher than that of Pt/C. The best urea/O 2 fuel cell performance was also observed with the MnFe 2 O 4 /GAs. The MnFe 2 O 4 /GAs exhibited an OCV of 0.713 V and a maximum power density of 1.7 mW cm −2 at 60 °C. Thus, this work shows that 3D structured graphene aerogel‐supported MnFe 2 O 4 catalysts can be used as an efficient cathode material for alkaline fuel cells.

Nanomaterials are the wonder materials in many distinguished fields, yet their research in mainstream Lithium-ion batteries is at rudimentary stages. Polyanion-based cathode materials use nanostructuring to enhance their performance throughput,...