An investigation was made of proton conduction in 2 gallate systems, La1−xBa1+xGaO4−x/2 and La1−xSr2+xGaO5−x/2, which contained tetrahedral Ga. Measurements performed in dry atmospheres showed that both systems exhibited a p-type contribution to conductivity. A comparison between dry and wet atmospheres revealed evidence of proton conduction. The La1−xBa1+xGaO4−x/2 system exhibited the highest proton conductivities; with the reported conductivities being significantly higher (about 10−4S/cm at 500C for x = 0.2) than those for other structures containing tetrahedral ions. Replacement of La by Pr in this system led to an increase in the electronic contribution to the conductivity.

Investigation of Proton Conduction in La1−xBa1+xGaO4−x/2 and La1−xSr2+xGaO5−x/2. F.Schönberger, E.Kendrick, M.S.Islam, P.R.Slater: Solid State Ionics, 2005, 176[39-40], 2951-3