Transport mixed protonic-electronic conductors

Tab. 2.2 S ummary of transport numbers of various mixed protonic-electronic conductors in various gas concentration cells. 

Proton-conducting materials [38-47], analogous to oxygen conductors but with stationary oxygen anions, can show mixed protonic-electronic conductivity, without considerable oxygen transport in hydrogen or water atmospheres [40,41], These materials have not been widely studied in comparison... 

Ceramic electrochemical reactors are currently undergoing intense investigation, the aim being not only to generate electricity but also to produce chemicals. Typically, ceramic dense membranes are either pure ionic (solid electrolyte SE) conductors or mixed ionic-electronic conductors (MIECs). In this chapter we review the developments of cells that involve a dense solid electrolyte (oxide-ion or proton conductor), where the electrical transfer of matter requires an external circuitry. When a dense ceramic membrane exhibits a mixed ionic-electronic conduction, the driving force for mass transport is a differential partial pressure applied across the membrane (this point is not considered in this chapter, although relevant information is available in specific reviews). 

Virkar, A.V. (2001) Transport of H2, O2 and H2O through single-phase, two-phase and multi-phase mixed proton, oxygen and electron hole conductors. Solid State Ionics, 140, 275-83. 

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