A proton conductor is an
electrolyte, typically a
solid electrolyte, in which movable
hydrogen ions (protons) are the primary charge carriers.Proton conductors are usually composed of polymer or ceramic because the pore size is small enough that larger negative ions are locked into the solid matrix, and only very small ions (positive hydrogen ions — bare
protons) can participate in a
direct current.Proton conductors are usually solid materials. When in the form of thin
membranes, proton conductors are an essential part of small, inexpensive
fuel cells.
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