Fig. 5.

(A) Increase in the intrinsic CO current density with increasing partial pressure of CO₂. The intrinsic reaction order with respect to CO₂ is 1.49 at −0.9 V vs. RHE, 1.63 at −1.0 V vs. RHE, and 1.83 at −1.1 V vs. RHE. (B) Increase in the extrinsic CO current density with increasing partial pressure of CO₂. The measured current density was obtained from cyclic voltammogram of CO₂RR over polycrystalline Ag at −1 V vs. RHE. The simulated apparent reaction order of 1.58 agrees well with the measured apparent order of 1.56. (C) The decrease in the CO and H₂ current densities with increasing pH of the electrolyte.