A Study on Sc2O3-Stabilized Zirconia Obtained by MOCVD as a Potential Electrolyte for Solid Oxide Fuel Cells

Dense, crack-free thin films (<5mm) of the nanostructured scandia-zirconia system (Sc2O3:ZrO2) stabilized in the cubic-fluorite phase (c-ZrO2) are deposited through conventional low-pressure metal-organic(LP-MO) CVD by using ?-diketonate metal complexes as precursors [(Zr(tmhd)4 and Sc(tmhd)3, with -tmhd = 2,2,6,6-tetramethyl-3,5-heptanedionate]. The compositional (energy dispersive X-ray spectroscopy - EDX), structural (X-ray diffraction - XRD) and morphological (field emission gun-environmental scanning electronmicroscopy - FEG-ESEM) analyses, confirmed the growth of dense partially and fully stabilized ZrO2, a suitable electrolyte for solid oxide fuel cells (SOFC). Results of impedance spectroscopy, which investigates the electrical conductivity of coating, deposited as thin as possible to guarantee the uniformcovering of a porous substrate, are reported. Results of thin films of yttria-zirconia system (Y2O3:ZrO2), deposited with the same method, are also reported for comparison.