The Tafel-Volmer path Characteristic for this path is that only one step includes an electron transfer. Only when the Volmer step is the rds, can one expect B-V type reaction kinetics. However, at sufficiently high overpotentials, the Volmer step will overtake the Tafel step, and one finds a limiting current corresponding to the dissociative adsorption of hydrogen (Fig. ). Note how the intermediate of the rds, 𝜃 or (1 -𝜃 -𝜃 𝑥 ), remains logarithmically constant in the constant-coverage-Tafel regions. Notably, when the Tafel step is the rds, the slope in the micropolarization region must be negative (Eq. 31g) as the intermediate coverage of hydrogen decreases with potential, the Tafel step being unable to replenish hydrogen coverage at the same rate, resulting in a