Fabrication of Thin-Film Yttria-Stabilized Zirconia Electrolyte by Aerosol-Assisted Chemical Vapor Deposition

Thursday, 30 July 2015
Hall 2 (Scottish Exhibition and Conference Centre)
D. Y. Jang (Korea University), M. Kim (School of Mechanical Engineering, Korea University), H. J. Kim, K. Bae, J. W. Kim, and J. H. Shim (Korea University)
Solid oxide fuel cells (SOFCs) are one of the most promising fuel cells because of their cost-effective materials, high efficiency, and fuel flexibility. However, the high operating temperature of SOFCs (>800°C) hinders their practical use. Performance enhancement by reducing the electrolyte thickness using thin-film deposition techniques may solve this drawback, because the large ohmic resistance of ion transport through the solid electrolyte lattice is the main factor increasing SOFCs’ operating temperature; this can be dramatically decreased with a thin electrolyte. Aerosol-assisted chemical vapor deposition (AACVD) uses aerosol droplets to transport high-mass precursors with reactive carrier gases. AACVD provides the opportunity to produce multicomponent materials at higher deposition rates with a cost-effective system compared to other thin-film deposition techniques. In this work, fully dense thin yttria-stabilized zirconia (YSZ) electrolyte films less than 1 μm thick were successfully fabricated by AACVD on the anode-supported SOFCs. For the AACVD, Zr(acac)4 (acac=acetylacetonate) and Y(acac)3 precursors were used as a solution in ethanol. High-purity N2 was used as the carrier gas, and the substrates were heated to 450°C during the deposition. As a result, good fuel cell performance with a maximum power of 80‒590 mW/cm2 was obtained at 450‒600°C. The details of the microstructures of our films and cells, together with the electrochemical performance evaluated from SOFCs with these AACVD YSZ electrolytes, will be presented at the session.