| In this paper,three-dimensionally ordered macroporous(3DOM) ytttiun-doped zirconium (YSZ) and gadolinia-doped ceria (CGO) were fabricated by using colloid crystal template of polystyrene (PS).The PS colloidal crystals were assembled successfully by several different methods, including gravitation sedimentation, centrifugation sedimentation and vertical deposition. SEM images showed that the PS spheres are well ordered close-packed structures by using vertical deposition method.The influence of temperature, colloidal concentration, humidity and additive on the quality of PS colloidal crystal template were investigated. Two array fashions, hexagonal and square arrays of the colloids were observed by SEM images. The influence of the experimental conditions on the array fashion and the formation of cracks and points defects were also investigated. PS colloidal thin films displayed bright iridescence due to Bragg diffraction. From the transmission spectra of PS crystals, photonic bands were stable when colloidal concentration was 0.1%. The spheres diameters correlated directly with the photonic bands position, according with the Bragg's law.Stable YSZ and CGO precursor solutions were prepared by using organic gel method, which were characterized by TG-DTA, XRD, FTIR and XPS. It is indicated the thin film calcined at 600℃was cubic structure and consisted of nanometer grains.A dip-drawing method had been used for the infiltration of YSZ and CGO precursor into PS template to fabricate 3DOM YSZ and CGO films. The concentration of CGO precursor and the infiltration times had important effects on the formation of ordered porous structure. In our experiment, good quality of the 3DOM could obtained with the concentration of sol 0.3～0.4mo1/L and two dipping times. High concentration and futher infiltrations would lead to a delamination of the films. The composite was calcined at 600℃for 2h to remove PS template and form 3DOM YSZ and CGO materials.
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