Fig. 3: Free-Energy Diagrams and Mechanistic Schemes for Conventional OER Mechanisms.
From: Oxygen evolution reaction on IrO2(110) is governed by Walden-type mechanisms
Free-energy diagram for the a mononuclear mechanism, c bifunctional I mechanism, and e bifunctional II mechanism on the fully hydroxylated IrO2(110) surface at 1.23 V and 1.53 V vs. RHE. The reaction intermediates of the mechanistic cycle are labeled on the x-axis. Blue and green solid lines indicate intermediates’ free energies at 1.23 V and 1.53 V, respectively. Colored arrows indicate the free-energy span governing Gmax(U), with the respective value displayed. b, d, f Schematic illustration of the mononuclear, bifunctional I, and bifunctional II mechanisms, as described in Section 3, on the fully hydroxylated IrO2(110) surface. Numbers next to the arrows indicate the step sequence, and each structure represents the corresponding reaction intermediate.
