Moreover, the influence of the LRE is unavoidable due to the presence of the EDL. We depict the LRE effects on the Tafel slopes of the ORR in Figure and of the CO2RR in Figure . Mass transport effects tend to increase the Tafel slope with increasing current density, especially for reactions with low reactant concentration in bulk solution (e.g., CO2RR), due to the concentration decrease at surface. At low overpotentials, the EDL effects are usually predominant. For instance, the intrinsic Tafel slope is 39 mV/dec for the ORR at 0.9 V and the CO2RR at -0.3 V, while the apparent Tafel slope is close to 59 mV/dec due to the EDL effects. However, 39 mV/dec and 59 mV/dec imply different RDSs in the conventional analysis. Furthermore, lateral interactions from competitive adsorbates and surface charging effects on adsorption energies are revealed as significant influences on the Tafel slope.