Well entrapped platinum-iron nanoparticles on three-dimensional nitrogen-doped ordered mesoporous carbon as highly efficient and durable catalyst for oxygen reduction and zinc-air battery.

The high-performance and durable oxygen reduction reaction (ORR) catalyst on air cathode is a key component in assembly of Zn-air batteries. Herein, three-dimensional N-doped ordered mesoporous carbon (3D N-OMC) was first prepared with silica as a template via pyrolysis with assistance of dicyandiamide as a N-doping agent, combined by full adsorption of platinum (II) acetylacetonate (Pt(acac)) and iron (II) phthalocyanine (FePc) via π-π interactions. After further pyrolysis of the resulting mixture, many PtFe nanoparticles were efficiently incorporated in 3D N-OMC (termed as PtFe@3D N-OMC for simplicity). Control experiments were certificated the important role of the pyrolysis temperature played in this synthesis. The resultant composite synergistically combines advantages of hierarchically accessible surfaces, highly open structure, and well-dispersed PtFe particles, which endow the PtFe@3D N-OMC with onset and half-wave potentials of 0.98 and 0.86 V in alkaline media, respectively, showing appealing catalytic activity for the ORR. Most significantly, the PtFe@3D N-OMC based Zn-air battery has a high power density of 80.57 mW cm and long-term durability (220 h, 660 cycles). This work opens a new avenue for design of high-efficiency and durable ORR electrocatalysts in energy conversion and storage systems.