Fabrication of Gd2O3-doped CeO2 thin films through DC reactive sputtering and their application in solid oxide fuel cells

Physical vapor deposition (PVD) can be used to produce high-quality Gd2O3-doped CeO2 (GDC) films. Among various PVD methods, reactive sputtering provides unique benefits, such as high deposition rates and easy upscaling for industrial applications. GDC thin films were successfully fabricated through reactive sputtering using a Gd0.2Ce0.8 (at%) metallic target, and their application in solid oxide fuel cells, such as buffer layers between yttria-stabilized zirconia (YSZ)/La0.6Sr0.4Co0.2Fe0.8O3-delta and as sublayers in the steel/coating system, was evaluated. First, the direct current (DC) reactive-sputtering behavior of the GdCe metallic target was determined. Then, the GDC films were deposited on NiO-YSZ/YSZ half-cells to investigate the influence of oxygen flow rate on the quality of annealed GDC films. The results demonstrated that reactive sputtering can be used to prepare thin and dense GDC buffer layers without high-temperature sintering. Furthermore, the cells with a sputtered GDC buffer layer showed better electrochemical performance than those with a screen-printed GDC buffer layer. In addition, the insertion of a GDC sublayer between the SUS441 interconnects and the Mn-Co spinel coatings contributed to the reduction of the oxidation rate for SUS441 at operating temperatures, according to the area-specific resistance tests.

Automated summary

Physical vapor deposition (PVD) is a suitable method for producing high-quality Gd2O3-doped CeO2 (GDC) films, with reactive sputtering being a preferred method due to its high deposition rates and scalability for industrial applications. GDC thin films were successfully fabricated through reactive sputtering and evaluated for their application in solid oxide fuel cells. The results showed that reactive sputtering can produce thin and dense GDC buffer layers without the need for high-temperature sintering, leading to improved electrochemical performance compared to screen-printed buffer layers. Furthermore, the inclusion of GDC sublayers in the steel/coating system reduced the oxidation rate for SUS441 at operating temperatures.