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Adsorption of water at the SrO surface of ruthenates.

ABSTRACT: Although perovskite oxides hold promise in applications ranging from solid oxide fuel cells to catalysts, their surface chemistry is poorly understood at the molecular level. Here we follow the formation of the first monolayer of water at the (001) surfaces of Sr(n+1)Ru(n)O3(n+1) (n = 1, 2) using low-temperature scanning tunnelling microscopy, X-ray photoelectron spectroscopy, and density functional theory. These layered perovskites cleave between neighbouring SrO planes, yielding almost ideal, rocksalt-like surfaces. An adsorbed monomer dissociates and forms a pair of hydroxide ions. The OH stemming from the original molecule stays trapped at Sr-Sr bridge positions, circling the surface OH with a measured activation energy of 187 ± 10?meV. At higher coverage, dimers of dissociated water assemble into one-dimensional chains and form a percolating network where water adsorbs molecularly in the gaps. Our work shows the limitations of applying surface chemistry concepts derived for binary rocksalt oxides to perovskites.

SUBMITTER: Halwidl D

PROVIDER: S-EPMC4817238 | biostudies-literature | 2016 Apr

REPOSITORIES: biostudies-literature

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Adsorption of Phospholipids at the Air-Water Surface.

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| S-EPMC6818144 | biostudies-literature

Antibody adsorption on the surface of water studied by neutron reflection.

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| S-EPMC5384797 | biostudies-literature

Elucidating the mechanism of selective ion adsorption to the liquid water surface.

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| S-EPMC4853788 | biostudies-literature

Impacts of Surface Adsorption on Water Uptake within a Metal Organic Nanotube Material.

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| S-EPMC9686127 | biostudies-literature

Structure and Undulations of Escin Adsorption Layer at Water Surface Studied by Molecular Dynamics.

Project description:The saponin escin, extracted from horse chestnut seeds, forms adsorption layers with high viscoelasticity and low gas permeability. Upon deformation, escin adsorption layers often feature surface wrinkles with characteristic wavelength. In previous studies, we investigated the origin of this behavior and found that the substantial surface elasticity of escin layers may be related to a specific combination of short-, medium-, and long-range attractive forces, leading to tight molecular packing in the layers. In the current study, we performed atomistic molecular dynamics simulations of 441 escin molecules in a dense adsorption layer with an area per molecule of 0.49 nm2. We found that the surfactant molecules are less submerged in water and adopt a more upright position when compared to the characteristics determined in our previous simulations with much smaller molecular models. The number of neighbouring molecules and their local orientation, however, remain similar in the different-size models. To maintain their preferred mutual orientation, the escin molecules segregate into well-ordered domains and spontaneously form wrinkled layers. The same specific interactions (H-bonds, dipole-dipole attraction, and intermediate strong attraction) define the complex internal structure and the undulations of the layers. The analysis of the layer properties reveals a characteristic wrinkle wavelength related to the surface lateral dimensions, in qualitative agreement with the phenomenological description of thin elastic sheets.

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Project description:Ecological Description of enteric viruses in Asipa River, Oyo

| PRJNA804916 | ENA

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Project description:surface water Raw sequence reads

| PRJNA438408 | ENA

Influence of Excess Charge on Water Adsorption on the BiVO<sub>4</sub>(010) Surface.

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Water Adsorption at the Tetrahedral Titania Surface Layer of SrTiO<sub>3</sub>(110)-(4 × 1).

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| S-EPMC3864247 | biostudies-literature

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