The Structural Optimization of Ceramic Fuel Cells

Abstract

The paper addresses questions concerning the structural optimization of ceramic fuel cells (CFC) aiming to increase the ionic conductivity realized at long term operation of zirconia electrolyte in the very structure of CFC applying scandia as the stabilizer of zirconia cubic phase and electron beam physical vapor deposition as the production method of the CFC's electrolyte film. Its chemical composition would be optimized in a course of a few iteration processes of a substance transfer from virgin powders into the electrolyte phase of CFC laminated composite, which is changed by diffusion processes between CFC electrolyte and its electrode layers during CFC production and long-term operation. The final, optimized, chemical composition and structure of entire CFC would be tuned by taking into account the structural altering occurring during both production and operation.

Nanocrystalline Cubic Phase Scandium-Stabilized Zirconia Thin Films

“…The cubic zirconia demonstrates exceptional properties, such as high hardness [ 4 ] and dielectric constant [ 5 ], superior chemical stability [ 6 ], and prominent optical characteristics [ 7 ]. As a result, ZrO 2 films have been exploited for a broad range of applications, e.g., wear-resistant coatings, medical implantology [ 8 ], oxygen detectors [ 9 ], thermal barrier coatings [ 10 , 11 , 12 ], solid electrolytes [ 13 , 14 , 15 ], and coatings for lenses and windows [ 16 ]. However, it is impossible to exploit pure zirconia in most of the above applications because of the high-temperature requirements of the c-phase existence.…”

“…Plenty of works study the structure of YSZ and ScSZ thin films, but again, only for specific concentrations of dopants [ 38 , 42 ]. The authors of [ 1 , 13 , 43 ] demonstrate that the film thickness, deposition, and annealing conditions are the key factors determining its structure, morphology, and, consequently, physical properties. In this regard, magnetron co-sputtering is an effective method for depositing bi- and three-component ZrO 2 -based thin films in a wide range of mutual concentrations for a thorough study of their structure and properties.…”

“…Presently, for developing highly efficient and stable solid oxide fuel cells (SOFC), the magnetron sputtering method is used to synthesize compact solid electrolytes in several laboratories [ 2 , 13 , 15 , 44 ]. It should be noted that mainly YSZ electrolytes are synthesized; in most cases, YZr composite metal targets are used in the sputtering process, the Y content of which varies from 15 to 20 at%.…”