Sealing of porous YSZ samples with Gd-doped CeO2 film produced using aqueous metal-EDTA complex solution

Abstract In this study, we propose a method for sealing porous samples using aqueous solutions of metal-ethylenediaminetetraacetic acid (EDTA) complexes. Gd-doped ceria (GDC) films were synthesized on porous NiO-mixed yttria-stabilized zirconia (YSZ) samples by coating them with a (Ce, Gd)-EDTA complex solution and subsequently sintering them in air at 850 °C for 1 h. When the Ce/Gd ratio in EDTA was 0.8:0.2, only a crystalline Ce0.8Gd0.2O1.9 phase was formed on the surface. The obtained results confirmed that the proposed treatment is effective for sealing the surfaces and open pores of porous samples. Finally, it was observed that a GDC layer was formed both at the sample surface and within the pores smaller than 1.7 μm.