Development and characterization of thin-film perovskite membranes with oxygen permeability.

ABSTRACTTwo conceptions of oxygen selective membrane's development, ceramic and thin film ones were considered using perovskite Ba0.5Sr0.5Co0.8Fe0.2O3−δ (BSCF) with mixed oxygen ionic and electronic conductivity. The films of BSCF (2–3mkm thick) were deposited by a MOCVD technique on the porous substrates (YSZ, Al2O3). Gas tightness, selective oxygen flux at 750–950°C and stability of the asymmetric film membranes in working conditions were investigated in comparison with ceramic ones. Sufficiently gas tight films can be directly obtained only on the substrates with submicron pores and at Tdep < 600°C. New alternative approach of large-pore substrates modification for obtaining gas-tight oxygen selectively permeable membranes was developed. To avoid the chemical interaction between BSCF and YSZ or Al2O3 the intermediate layer of BaO was pre-deposited. Resulting permeation through asymmetric membranes was thought to be dependent on oxygen exchange surface reaction and gas permeability of the porous supports.

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Selenization of CuInS2 by rapid thermal processing – an alternative approach to induce a band gap grading in chalcopyrite thin-film solar cell absorbers?

Journal of Materials Chemistry A ◽

10.1039/c8ta10823d ◽

2019 ◽

Vol 7 (5) ◽

pp. 2087-2094 ◽

Cited By ~ 1

Author(s):

Roberto Félix ◽

Alfons Weber ◽

Ole Zander ◽

Humberto Rodriguez-Álvarez ◽

Björn-Arvid Schubert ◽

...

Keyword(s):

Thin Film ◽

Solar Cell ◽

Band Gap ◽

Thermal Processing ◽

Thin Film Solar Cell ◽

Rapid Thermal Processing ◽

Alternative Approach

Characterization of selenium-treated CuInS2 reveals a band gap grading and a surface Cu enrichment, opening new chalcopyrite absorber tailoring opportunities.

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Characterization of Crystalline Structure and Morphology of Ga2O3 Thin Film Grown by MOCVD Technique

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.721.253 ◽

2016 ◽

Vol 721 ◽

pp. 253-257

Author(s):

Alvars Kjapsna ◽

Lauris Dimitrocenko ◽

Ivars Tale ◽

Anatoly Trukhin ◽

Reinis Ignatans ◽

...

Keyword(s):

Thin Film ◽

Gallium Oxide ◽

Growth Process ◽

Oxygen Vacancies ◽

Oxide Thin Film ◽

Structure And Morphology ◽

Carrier Gases ◽

Compositional Properties ◽

Mocvd Technique

Growth of gallium oxide thin film was realized with MOCVD on (0001) sapphire substrate. Structural and compositional properties of thin film were studied employing trimethylgallium and water as precursors, carrier gases were H2 and N2. Obtained film is polycrystalline and predominantly consisted of (201) oriented β-Ga2O3. Sample exhibited blue luminescence which is attributed to oxygen vacancies. H2 gas proved to have beneficial effect on film quality and overall growth process.

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Linking the Electrical Conductivity and Non-Stoichiometry of Thin Film Ce1−xZrxO2−δ by a Resonant Nanobalance Approach

Materials ◽

10.3390/ma14040748 ◽

2021 ◽

Vol 14 (4) ◽

pp. 748

Author(s):

Iurii Kogut ◽

Alexander Wollbrink ◽

Carsten Steiner ◽

Hendrik Wulfmeier ◽

Fatima-Ezzahrae El Azzouzi ◽

...

Keyword(s):

Thin Film ◽

Thin Films ◽

Electrical Conductivity ◽

High Temperature ◽

Electronic Conductivity ◽

Oxygen Storage ◽

Partial Pressures ◽

Maximum Conductivity ◽

Defect Interactions

Bulk ceria-zirconia solid solutions (Ce1−xZrxO2−δ, CZO) are highly suited for application as oxygen storage materials in automotive three-way catalytic converters (TWC) due to the high levels of achievable oxygen non-stoichiometry δ. In thin film CZO, the oxygen storage properties are expected to be further enhanced. The present study addresses this aspect. CZO thin films with 0 ≤ x ≤ 1 were investigated. A unique nano-thermogravimetric method for thin films that is based on the resonant nanobalance approach for high-temperature characterization of oxygen non-stoichiometry in CZO was implemented. The high-temperature electrical conductivity and the non-stoichiometry δ of CZO were measured under oxygen partial pressures pO2 in the range of 10−24–0.2 bar. Markedly enhanced reducibility and electronic conductivity of CeO2-ZrO2 as compared to CeO2−δ and ZrO2 were observed. A comparison of temperature- and pO2-dependences of the non-stoichiometry of thin films with literature data for bulk Ce1−xZrxO2−δ shows enhanced reducibility in the former. The maximum conductivity was found for Ce0.8Zr0.2O2−δ, whereas Ce0.5Zr0.5O2-δ showed the highest non-stoichiometry, yielding δ = 0.16 at 900 °C and pO2 of 10−14 bar. The defect interactions in Ce1−xZrxO2−δ are analyzed in the framework of defect models for ceria and zirconia.

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Characterization of Y-Ba-Cu-O films grown on silicon substrates by sequential evaporation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100106399 ◽

1988 ◽

Vol 46 ◽

pp. 866-867

Author(s):

E. L. Hall ◽

A. Mogro-Campero ◽

L. G. Turner ◽

N. Lewis

Keyword(s):

Thin Film ◽

Thin Film Deposition ◽

Superconducting Films ◽

Electron Beam Evaporation ◽

Film Deposition ◽

Silicon Substrates ◽

Superconducting Properties ◽

Sequential Electron ◽

Thin Superconducting Films

There is great interest in the growth of thin superconducting films of YBa2Cu3Ox on silicon, since this is a necessary first step in the use of this superconductor in a variety of possible electronic applications including interconnects and hybrid semiconductor/superconductor devices. However, initial experiments in this area showed that drastic interdiffusion of Si into the superconductor occurred during annealing if the Y-Ba-Cu-O was deposited direcdy on Si or SiO2, and this interdiffusion destroyed the superconducting properties. This paper describes the results of the use of a zirconia buffer layer as a diffusion barrier in the growth of thin YBa2Cu3Ox films on Si. A more complete description of the growth and characterization of these films will be published elsewhere.Thin film deposition was carried out by sequential electron beam evaporation in vacuum onto clean or oxidized single crystal Si wafers. The first layer evaporated was 0.4 μm of zirconia.

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Microstructural and fractographic characterization of B4C-Al cermets tested under dynamic and static loading

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100154780 ◽

1989 ◽

Vol 47 ◽

pp. 562-563

Author(s):

Gyeung Ho Kim ◽

Mehmet Sarikaya ◽

D. L. Milius ◽

I. A. Aksay

Keyword(s):

Thin Film ◽

Mechanical Properties ◽

Fracture Toughness ◽

Static Loading ◽

Carbon Deposition ◽

Full Density ◽

Unique Combination ◽

Strong Component ◽

Reaction Products

Cermets are designed to optimize the mechanical properties of ceramics (hard and strong component) and metals (ductile and tough component) into one system. However, the processing of such systems is a problem in obtaining fully dense composite without deleterious reaction products. In the lightweight (2.65 g/cc) B4C-Al cermet, many of the processing problems have been circumvented. It is now possible to process fully dense B4C-Al cermet with tailored microstructures and achieve unique combination of mechanical properties (fracture strength of over 600 MPa and fracture toughness of 12 MPa-m1/2). In this paper, microstructure and fractography of B4C-Al cermets, tested under dynamic and static loading conditions, are described.The cermet is prepared by infiltration of Al at 1150°C into partially sintered B4C compact under vacuum to full density. Fracture surface replicas were prepared by using cellulose acetate and thin-film carbon deposition. Samples were observed with a Philips 3000 at 100 kV.

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