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Diffusion and Film Mass Transport

To model a porous electrocatalyst we may consider a second type of mass transport (in addition to diffusion) locally within the electrode, i.e., a mass transport resistance between the electrode surface and the solution. This situation may arise, for example, when the electrode surface is covered by a thin layer of polymer electrolyte or as in a fuel cell electrode in which the electrocatalyst is also covered by a thin water layer. [Pg.244]

The mass transfer conditions between the fluid phase and fixed phase are assumed to be uniform, as defined by a single mass transport coefficient. Then Eq. (43) should be rewritten as [Pg.244]

Introducing the mass transfer parameter, for the Tafel type reaction, assuming migration is negligible, the local flux will be [Pg.245]

With the value of a constant, Eq. (75) is a linear problem for which an analytical solution can be obtained [Pg.246]

The situation is also similar to the role of diffusion in a porous catalyst pellet if Eq. (75) is written as [Pg.246]


See other pages where Diffusion and Film Mass Transport is mentioned: [Pg.244]    [Pg.244]   


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