English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Y-doped BaZrO$_3$ is a promising proton conductor for intermediatetemperature solid oxide fuel cells. In this work, a combination of static DFTcalculations and DFT based molecular dynamics (DFT-MD) was used to study protonconduction in such a material. Geometry optimisations of 100 structures with a12.5% dopant concentration allowed us to identify a clear correlation betweenthe bending of the metal-oxygen-metal angle and the energies of the simulatedcells. Depending on the type of bending, two configurations, designated asinwards bending and outwards bending, were defined. The results demonstratethat a larger bending decreases the energy and that the lowest energies areobserved for structures combining inwards bending with protons being close tothe dopant atoms. These lowest energy structures are the ones with thestrongest hydrogen bonds. DFT-MD simulations in cells with different yttriumdistributions provide complementary microscopic information on proton diffusionas they capture the dynamic distortions of the lattice caused by thermalmotion. A careful analysis of the proton jumps between different environmentsconfirmed that the inwards and outwards bending states are relevant for theunderstanding of proton diffusion. Indeed, intra-octahedral jumps were shown toonly occur starting from an outwards configuration while the inwardsconfiguration seems to favor rotations around the oxygen. On average, in theDFT-MD simulations, the hydrogen bond lengths are shorter for the outwardsconfiguration which facilitates the intraoctahedral jumps. Diffusioncoefficients and activation energies were also determined and compared toprevious theoretical and experimental data showing a good agreement withprevious data corresponding to local proton motion.

Local distortions and dynamics in hydrated Y-doped BaZrO$_3$