Improvement of oxygen-ionic and protonic conductivity of BaLaInO4 through Ti doping

Abstract

The solid solution BaLaIn1–хTiхO4+0.5х (0 ≤ x ≤ 0.15) with the Ruddlesden-Popper structure was obtained. It was proved that significant proton concentration is achieved by up to 1.25 mol H2O. The degree of hydration increased with increasing the dopant concentration and was determined by the size of the salt block. The Ti doping of BaLaInO4 led to the increase in the ionic (O2−, H+) conductivities up to ~ 1.5 orders of magnitude. The sample BaLaIn0.9Ti0.1O4.05 (x = 0.10) exhibited nearly pure oxygen-ionic (pH2O = 3.5·10−5 atm) and protonic (pH2O = 2·10−2 atm) transport at T < 400 °C and T < 450 °C, correspondingly.