Proton-Electron Mixed Conduction Properties in (Ce,Sr)PO4

Abstract

Mixed conductivity of proton and electron hole in (Ce,Sr)PO4 have been investigated by electrical conductivity and hydrogen permeation measurements. The partial conductivity contributions of proton and electron hole were separately evaluated from the total conductivity by assuming the defect model proposed in the preceding work. Hydrogen permeation measurements were demonstrated in order to check if and how much hydrogen permeates across the (Ce,Sr)PO4 membranes. As expected, hydrogen successfully permeated across the membranes. Use of surface catalysts was found to enhance the hydrogen permeation fluxes. This suggested that the contribution of the surface reaction to the hydrogen permeation process is remarkable. Hydrogen permeation flux through the (Ce,Sr)PO4 membranes is concluded to be essentially determined by the surface reaction process.