FeNi-functionalized 3D N, P doped graphene foam as a noble metal-free bifunctional electrocatalyst for direct methanol fuel cells

Designing high-performance bifunctional electrocatalysts for oxygen reduction (ORR) and methanol oxidation (MOR) reaction is essential for the wide application of direct methanol fuel cells. Here, we have prepared a novel three-dimensional (3D) FeNi-functionalized N, P doped graphene foam (FeNi@NP-GF) by a simple and cost-effective one-step pyrolysis method, as excellent bifunctional electrocatalyst for direct methanol fuel cells. Compared with metal-free and transition metal single-doped graphene foam catalysts (NP-GF, Fe@NP-GF and Ni@NP-GF), the resulting FeNi@NP-GF catalyst showed more positive half-wave potential and higher limiting current density in ORR reaction. Furthermore, it manifests a four-electron transfer process and strong methanol crossover resistance in the alkaline medium. The above results ascribed to the synergistic effect of Fe/Ni-Nx species formed with Fe/Ni and N species and multiple active sites in the 3D porous graphene material. Moreover, FeNi@NP-GF acted as good support for Pt nanoparticles (NPs). Pt/FeNi@NP-GF catalyst displayed remarkable catalytic performance and high stability for methanol electrooxidation reaction in acid medium. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

A novel 3D FeNi-functionalized N, P doped graphene foam electrocatalyst (FeNi@NP-GF) was prepared, showing enhanced catalytic performance in ORR reaction due to the synergistic effect of Fe/Ni and N species and multiple active sites in the 3D porous graphene material. Furthermore, FeNi@NP-GF also acted as a good support for Pt nanoparticles, exhibiting remarkable catalytic activity and high stability for methanol electrooxidation in acid medium.