Achieving excellent activity and stability for oxygen reduction electrocatalysis by hollow mesoporous iron–nitrogen-doped graphitic carbon spheres

Fe–N–C graphitic spheres preparedvia in situpolymerization and functionalization possess both chemical functions (Fe–N_x-coordinated moieties) and hollow mesoporous structures, demonstrating exceptional activity and stability for the 4e⁻oxygen reduction reaction in both acidic and alkaline media.