Crystal and Electronic Structures and High Temperature Protonic Conduction of LaBaGa0.95Mg0.05O4-[delta]

In this work, we synthesized LaBaGaO4 and LaBaGa0.95Mg0.05O4-δ, and investigated their crystal and electronic structures and electrical conduction properties. As a result, it was indicated that LaBaGaO4 had an orthorhombic structure (S.G.; P212121) at 298 and 900 K. The orthorhombic structure was kept even after Mg-doping although the electronic structure seemed to be varied maybe due to a partial substitution of Mg2+ for Ga3+. From an H/D isotope effect on conductivity, it was confirmed that LaBaGa0.95Mg0.05O4-δ exhibited protonic conduction at elevated temperatures under a moisturized condition.