fig5

Figure 5. (A) Schematic illustration of the catalyst layer structure with varying ionomer ratio; (B) FE_CO of GDEs with varying ionomer ratio at 300 mA cm^-2; (C) ECSA and (D) EIS of GDEs with varying ionomer ratio; (E) FE_CO of GDEs with D79 and D520 at different CO₂ concentration; (F) DRT plot of GDE with 20 wt% D79 at 100-500 mA cm^-2; (G) DRT plot of GDE with varying ionomer ratio at 300 mA cm^-2; (H) DRT plot of GDE with 20 wt% D79 at varying flow rates at 300 mA cm^-2; (I) DRT plot of GDE with 5wt% D79 and 40wt% D79 at 300 mA cm^-2. Error bars represent the standard deviation from three independent measurements. Note that the x-axes in panels F-I are presented in logarithmic (Log10) scale.