Interconnected 3D Fe3O4/rGO as highly durable electrocatalyst for oxygen reduction reaction

Abstract

Development of low-cost and high-efficient oxygen reduction reaction (ORR) catalyst is a crucial challenge in fuel cell technology. Herein, we proposed a simple and scalable strategy to fabricate an interconnected 3D Fe₃O₄/rGO composite, in which Fe₃O₄ nanoparticles mechanically anchor in reduced graphene oxide (rGO). Benefiting from its 3D layered structure with loose skeleton and rich porosity, and strong synergetic coupling between Fe₃O₄ nanoparticles and rGO, the prepared composite, Fe₃O₄/rGO, provides better catalytic performance for ORR compared with commercial Pt/C catalyst, featuring high limiting current density (4.6 mA cm⁻²) close to that of Pt/C (4.7 mA cm⁻²), low H₂O₂ yield (1%–6%), high electron transfer number (∼4), and outstanding long-term durability and methanol resistance in alkaline electrolytes. These encouraging results manifest that the Fe₃O₄/rGO composite holds great promise as a low-cost and high-performance alternative catalyst for ORR.