Characterizing chemical stability and proton conductivity of B-site doped barium hafnate (BaHfO3) and barium stannate (BaSnO3) with first principles modeling

Abstract

Perovskite-structured oxides are promising materials for proton conduction. We use first-principles calculations to investigate the chemical stability and proton conductivity of doped barium hafnate (BaHfO3) and barium stannate (BaSnO3). Previously, we [RSC Adv. 3, 3333 (2013)] reported first-principles calculations examining the chemical stability and proton conductivity of B-site doped BaZrO3 and found that Ga-doping gives the highest chemical stability and La-doping provides the highest proton conductivity in BaZrO3. We use density functional theory (DFT) calculations to examine two other host materials, BaHfO3 and BaSnO3, using these two dopants, Ga and La. We find that doped BaHfO3 is promising to study further in co-doping case, because Ga-doped BaHfO3 demonstrates the high stability and La-doped BaHfO3 shows the high proton conductivity compared to doped BaSnO3 and doped BaZrO3.