Biomass wood-derived efficient Fe–N–C catalysts for oxygen reduction reaction

Abstract

Efficient and low-cost electrocatalysts for oxygen reduction reaction (ORR) were the key for scalable application of metal–air batteries and fuel cells. Herein, iron-based nitrogen-doped carbon catalysts (Fe–N–Cwood) were prepared, using hydrothermal-pyrolysis-treated wood-derived nitrogen-doped carbon as the support. This support possessed large specific surface area and macro–meso–micro hierarchical porous networks, ensuring fluent mass transfer of electrolyte and oxygen species. In the ORR electrochemical test, Fe–N–Cwood catalyst showed an excellent activity, with a half-wave potential of 0.90 V in 0.1 M KOH, and a half-wave potential of 0.70 V in 0.1 M HClO4. Moreover, durability tests illustrated that Fe–N–Cwood possessed high stability and methanol tolerance. The Fe–N–Cwood-based Zn–air battery delivered a peak power density of 231 mW cm−2, suggesting its potential applications in sustainable energy conversion systems. A highly efficient ORR electrocatalyst was obtained by embedding iron nanoparticles with hydrothermal-pyrolysis-treated wood-derived carbon.