Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8024127 | Surface and Coatings Technology | 2018 | 8 Pages |
Abstract
Gadolinia-doped ceria (GDC) films are synthesized by direct current magnetron sputtering under reactive conditions for hydrogen production by high temperature electrolysis (HTE). First, the sputtering process is investigated by varying the reactive gas flow rate. Working conditions in elemental sputtering mode (ESM) are adjusted to ensure a high incorporation of oxygen while keeping a high deposition rate. Heat treatments in air are found necessary to stabilize the sub-stoichiometric deposited oxide. The main characteristics of the films (crystallinity, chemical composition, porosity, etc.) are studied by Rutherford backscattering spectroscopy (RBS), optical transmission spectroscopy, Raman spectroscopy, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and scratch test and are compared to that of a conventional 2â¯Î¼m thick GDC layer deposited by screen printing. The sputtered layer appears dense and adherent but kind of blisters are observed when deposited on half-cells. Performances of a thin GDC barrier layer (below 500â¯nm) sputter deposited on half cells are evaluated. Encouraging results are obtained since performances (i.e. about â1.70â¯A·cmâ2 at 1.3â¯V and 800â¯Â°C in HTE mode) are slightly higher to that typically achieved with a classical manufactured cell (i.e. about â1.65â¯A·cmâ2 at 1.3â¯V and 800â¯Â°C). A degradation rate of about 9% for 1000â¯h operation (at 800â¯Â°C with a current density of â0.5â¯A·cmâ2, GDC layer thickness of 425â¯nm) is achieved.
Related Topics
Physical Sciences and Engineering
Materials Science
Nanotechnology
Authors
Pierre Coddet, Julien Vulliet, Caroline Richard, Amael Caillard, Anne-Lise Thomann,