High proton conduction by full hydration in highly oxygen deficient perovskite

Abstract

Ceramic proton conductors are important in various applications such as fuel cells. In contrast to the conventional acceptor doping into the perovskite-type oxide without oxygen vacancies, donor doping into highly...

High Proton Conduction in the Octahedral Layers of Fully Hydrated Hexagonal Perovskite-Related Oxides

“…These results indicate that the high proton concentration y due to the large amount of oxygen vacancies in BEAS without water and the high fractional water uptake (full hydration) is the origin of the high proton conductivity in BEAS. Ba 2 In 2 O 6–2δ · y H 2 O , and doped barium zirconates and scandate such as BaZr 0.95 Y 0.05 O 3−δ ·( y /2)­H 2 O, BaZr 0.8 In 0.2 O 3−δ ·( y /2)­H 2 O, and BaSc 0.8 W 0.2 O 3−δ ·( y /2)­H 2 O exhibit full hydration ( F w = 1.0), as well as BEAS (Figure S16).…”

“…47 exhibit full hydration (F w = 1.0), as well as BEAS (FigureS16).Neutron diffraction (ND) data of dry Ba 5 Er 2 Al 2 SnO 13 and hydrated (deuterated) Ba 5 Er 2 Al 2 SnO 13−5y/2 (OD) 5y were measured at 5 K to investigate the bulk hydration, bulk proton concentration, and detailed crystal structure, including the occupancy and atomic coordinates of hydrogen and oxygen atoms. Rietveld refinement of the ND data of dry Ba 5 Er 2 Al 2 SnO 13 was successfully carried out using the crystal data of hexagonal P63 /mmc Ba 5 Er 2 Al 2 ZrO 12.77 (OH) 0.46 (= Ba 5 Er 2 Al 2 ZrO 13 •0.23 H 2 O) in ref 28 as initial parameters (Figure S17a and Table…”