Influence of Nonstoichiometry on Proton Conductivity in Thin-Film Yttrium-Doped Barium Zirconate.

Title Influence of Nonstoichiometry on Proton Conductivity in Thin-Film Yttrium-Doped Barium Zirconate.
Authors J. Ding; J. Balachandran; X. Sang; W. Guo; G.M. Veith; C.A. Bridges; C.M. Rouleau; J.D. Poplawsky; N. Bassiri-Gharb; P. Ganesh; R.R. Unocic
Journal ACS Appl Mater Interfaces
DOI 10.1021/acsami.7b16900
Abstract

Proton-conducting perovskites have been widely studied because of their potential application as solid electrolytes in intermediate temperature solid oxide fuel cells. Structural and chemical heterogeneities can develop during synthesis, device fabrication, or service, which can profoundly affect proton transport. Here, we use time-resolved Kelvin probe force microscopy, scanning transmission electron microscopy, atom probe tomography, and density functional theory calculations to intentionally introduce Ba-deficient planar and spherical defects and link the resultant atomic structure with proton transport behavior in both stoichiometric and nonstoichiometric epitaxial, yttrium-doped barium zirconate thin films. The defects were intentionally induced through high-temperature annealing treatment, while maintaining the epitaxial single crystalline structure of the films, with an overall relaxation in the atomic structure. The annealed samples showed smaller magnitudes of local lattice distortions because of the formation of proton polarons, thereby leading to decreased proton-trapping effect. This resulted in a decrease in the activation energy for proton transport, leading to faster proton transport.

Citation J. Ding; J. Balachandran; X. Sang; W. Guo; G.M. Veith; C.A. Bridges; C.M. Rouleau; J.D. Poplawsky; N. Bassiri-Gharb; P. Ganesh; R.R. Unocic.Influence of Nonstoichiometry on Proton Conductivity in Thin-Film Yttrium-Doped Barium Zirconate.. ACS Appl Mater Interfaces. 2018;10(5):48164823. doi:10.1021/acsami.7b16900

Related Elements

Zirconium

See more Zirconium products. Zirconium (atomic symbol: Zr, atomic number: 40) is a Block D, Group 4, Period 5 element with an atomic weight of 91.224. Zirconium Bohr ModelThe number of electrons in each of Zirconium's shells is 2, 8, 18, 10, 2 and its electron configuration is [Kr]4d2 5s2. The zirconium atom has a radius of 160 pm and a Van der Waals radius of 186 pm. Zirconium was discovered by Martin Heinrich Klaproth in 1789 and first isolated by Jöns Jakob Berzelius in 1824. In its elemental form, zirconium has a silvery white appearance that is similar to titanium. Zirconium's principal mineral is zircon (zirconium silicate). Elemental ZirconiumZirconium is commercially produced as a byproduct of titanium and tin mining and has many applications as a opacifier and a refractory material. It is not found in nature as a free element. The name of zirconium comes from the mineral zircon, the most important source of zirconium, and from the Persian wordzargun, meaning gold-like.

Barium

See more Barium products. Barium (atomic symbol: Ba, atomic number: 56) is a Block S, Group 2, Period 6 element with an atomic weight of 137.27. The number of electrons in each of barium's shells is [2, 8, 18, 18, 8, 2] and its electron configuration is [Xe] 6s2. Barium Bohr ModelBarium is a member of the alkaline-earth metals. The barium atom has a radius of 222 pm and a Van der Waals radius of 268 pm. Barium was discovered by Carl Wilhelm Scheele in 1772 and first isolated by Humphry Davy in 1808. Elemental BariumIn its elemental form, barium is a soft, silvery-gray metal. Industrial applications for barium include acting as a "getter," or unwanted gas remover, for vacuum tubes, and as an additive to steel and cast iron. Barium is also alloyed with silicon and aluminum in load-bearing alloys. The main commercial source of barium is the mineral barite (BaSO4); it does not occur naturally as a free element . The name barium is derived from the Greek word "barys," meaning heavy.

Yttrium

See more Yttrium products. Yttrium (atomic symbol: Y, atomic number: 39) is a Block D, Group 3, Period 5 element with an atomic weight of 88.90585. Yttrium Bohr ModelThe number of electrons in each of yttrium's shells is [2, 8, 18, 9, 2] and its electron configuration is [Kr] 4d1 5s2. The yttrium atom has a radius of 180 pm and a Van der Waals radius of 219 pm. Yttrium was discovered by Johann Gadolin in 1794 and first isolated by Carl Gustav Mosander in 1840. In its elemental form, Yttrium has a silvery white metallic appearance. Yttrium has the highest thermodynamic affinity for oxygen of any element. Elemental YttriumYttrium is not found in nature as a free element and is almost always found combined with the lanthanides in rare earth minerals. While not part of the rare earth series, it resembles the heavy rare earths which are sometimes referred to as the "yttrics" for this reason. Another unique characteristic derives from its ability to form crystals with useful properties. The name yttrium originated from a Swedish village near Vaxholm called Yttbery where it was discovered.

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