fig12

Figure 12. (A) Illustration of Fe-N-C-700^[157]; (B) Illustration of Fe₃C@N/MCHSs and Fe₃C-NG Mott-Schottky heterojunction; (C) Illustration of the Mott−Schottky heterojunction of the Fe₃C @NG: before and after contacting, and the ORR mechanism, the charge distribution of Fe₃C @NG model, the ORR processes on Fe₃C@NG model^[158]; (D) Illustration of Co/MnO@NC; (E) DFT calculations of Co-MnO^[156]. NG: N-doped graphene; ORR: oxygen reduction reaction; DFT: density functional theory; NTA: nitrilotriacetic acid.