Fuel Cell Membranes as Matrices for Aqueous Proton Transfer

Fuel Cell Membranes as Matrices for Aqueous Proton Transfer 

As we will see below, this briefly sketched mechanism of proton transfer in liquid water could be highly relevant for important types of PEMs under realistic operating conditions in the fuel cell. In many cases, in particular when it comes to advanced membrane design, it is, however, not enough to consider the membrane as an inert container for water pathways . Indeed, the dependence of membrane conductivity on the global or local water content is determined not only by the connectivity of the aqueous percolation network but also by the varying abUity of each pathway to conduct protons. 

A major incentive of this article will be to stress the complicating traits of the membrane environment on effective proton transport and fuel cell performance. The polymer affects distribution and structme of water and dynamics of protons and water molecules at multiple scales. In order to describe the conductivity of the membrane, one needs to take into account explicit polymer-water interactions at molecular level, interfacial phenomena at polymer-water interfaces at mesoscopic scale and the statistical geometry and topology of randomly distributed aqueous and polymeric domains at macroscopic scale. 

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