fig8

Figure 8. (A) HAADF-STEM images of Fe-N-C; (B) The TOF of different sites; (C) The normalized XANES spectra at the Fe K-edge of different samples^[74]. Copyright 2023, ACS Publications; (D) Specific current density of CO for Ni-N₃V, NiN₄ and NC; (E) The optimized structures of Ni SACs and the proposed reaction pathways of Ni-N₃-V for CO₂ electroreduction to CO^[21]. Copyright 2023, Wiley; (F) Energy profiles for the discharging process from S8 to Li₂S on the five catalyst models; (G) Energy profiles for the reduction of Li₂S on Ni-N₅/C^[77]. Copyright 2023, ACS Publications. HAADF-STEM: High-angle annular dark field scanning transmission electron microscopy; TOF: turnover frequency; XANES: X-ray absorption near edge structure; SACs: single atom electrocatalysts.