Facile synthesis of amino acids-derived Fe/N-codoped reduced graphene oxide for enhanced ORR electrocatalyst

Here, a simple and green synthesis process of Fe/N-codoped reduced graphene oxide (Fe-N-C/NG) with high electrocatalytic activity for oxygen reduction reaction (ORR) is reported. The synthesis of 3D porous structure of Fe-N-C/NG composites involves thermal drying the mixture of graphene oxide (GO), iron nitrate and aspartic acid (Asp) directly, follow by pyrolysis the mixture. The Asp is introduced as an environment-friendly nitrogen and carbon source, and the iron nitrate serves as the pore-forming agent and a gas producer that prevents the agglomeration of graphene. The as-prepared Fe-N-C/NG exhibits 3D loose porous structure with larger specific surface area (245 m(2) g(-1)). The Fe-NC/NG composite exhibits the onset potential of 0.91 V, a half-wave potential (E1/2 = 0.83 V), low Tafel slope and four-electron selectivity (n = 3.99) in alkaline solution. Furthermore, the stability test manifests the outstanding stability of Fe-NC/NG electrocatalyst and a superior methanol tolerance than Pt/C electrodes. Particularly, when the prepared Fe-NC/NG-3 catalyst is used as an air electrode catalyst in an assembled Zn-air battery, it exhibits a high specific capacity of 848.2 mAh gZ(n)(-1) and displays more stability than Pt/C. This work provides an effective strategy for preparing high ORR and Zn-air battery performance Fe/N-codoped reduced graphene oxide materials.

Automated summary

A simple and green synthesis process for Fe/N-codoped reduced graphene oxide materials with high electrocatalytic activity for oxygen reduction reaction (ORR) was reported. The synthesized material exhibited superior performance and stability, showing promising potential for application in zinc-air batteries.