fig11
From: Heterogeneous single-atom catalysts for energy process: recent progress, applications and challenges
Figure 11. (A) Schematic Fe SACs fabrication process by adsorbing Fe into N-doped carbon; no complex carbonization and nitrogen-doping processes occurred during thermal activation; (B) ORR polarization plots in 0.5 M H2SO4 electrolyte; (C) Fuel cell performance of the best-performing Fe SAC under both H2/O2 and H2/air conditions. Reproduced from Ref.[124] with permission from Wiley-ACH. (D) Aberration-corrected HAADF-STEM image of the Zn-NC-1 catalyst; (E) HRTEM image of the Zn-NC-1 catalyst; ORR polarization curves of Zn-N-C-X and Fe-N-C-X catalysts recorded in O2-saturated 0.1 M HClO4 (F) and 0.1 M KOH solution (G); Reproduced from Ref.[125] with permission from Wiley-ACH.
