By directly examining fuel-cell performances, it was found that non oxide-containing materials such as chlorides and fluorides exhibited appreciable proton and O-ion conductivities. Ionic transport measurements showed that both proton and O-ion conduction occurred; with proton conduction predominating in most cases. The steady-state current output under fuel-cell operating conditions indicated that the transport process in both chloride and fluoride electrolytes was dominated by source ions, protons and O ions. The new materials were expected to have a significant importance to both fundamental and applied research.

Proton and Oxygen Ion Conduction in Non-Oxide Ceramics. B.Zhu: Materials Research Bulletin, 2000, 35[1], 47-52