Protonic transport in the new phases BaLaIn0.9M0.1O4.05 (M=Ti, Zr) with Ruddlesden-Popper structure

The new proton-conducting phases BaLaIn0.9M0.1O4.05 (M = Ti, Zr) with Ruddlesden-Popper structure were obtained. The substitution of In3+ ions by the Ti4+ and Zr4+ ions leads to the expansion of the ab plane due to the incorporation of the oxygen interstitials in the La–O rock-salt blocks. It was established that all investigated samples were capable for the water uptake from the gas phase due to the presence in the structure of La–O blocks. The degree of hydration increased with an increase in the size of the salt blocks. It was proved that doping led to the increase in the oxygen ionic conductivity due to the formation of interstitial oxygen. The conductivity values for doped sample BaLa0.9M0.1InO3.95 were higher than for undoped composition BaLaInO4 by ~1 order of magnitude. The new phases BaLaIn0.9M0.1O4.05 (M = Ti, Zr) demonstrate the predominant protonic conductivity at Т