fig7

Figure 7. (A) Kinetic current density of electrocatalysts at 0.80 and 0.85 V^[65]. Copyright 2023, Wiley-VCH; (B) PEMFC polarization and power density curves of Fe₂-S₁N₅N₅/SNC^[92]. Copyright 2024, The Royal Society of Chemistry; (C) LSV polarization curves of the ORR in O₂-saturated 0.1 M KOH solution^[93]. Copyright 2024, The Royal Society of Chemistry; (D) Schematic illustration of the single-site catalytic mechanism for PdCu (left) and multi-site tandem mechanism for PdCu-Fe₃O₄ (right)^[95]. Copyright 2024, Wiley-VCH. PEMFC: Proton exchange membrane fuel cell; LSV: linear sweep voltammetry; ORR: oxygen reduction reaction.