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LaCrO 3 thin films on electrolyte yttria-stabilized zirconia (YSZ) substrates were prepared by spray pyrolysis technique in the temperature range of 600–750 °C using lanthanum and chromium nitrates as precursors. Thin films obtained at 600–650 °C appear to be a mixture of cubic La(OH)CrO 4 and cubic LaCrO 4 phases, which transforms to pure cubic LaCrO 4 with the substrate temperature increasing to 700–750 °C. After being annealed at 900 °C for 2 h, all films convert to a single cubic LaCrO 3 phase. The change of Cr2p spectra in X-ray photoelectron spectroscopy (XPS) analysis shows the similar phase transformation process. Reaction processes with respect to the substrate temperature were proposed according to X-ray diffraction (XRD) and XPS analysis. The surface morphology of the films was found to depend strongly on the substrate temperature, which would be the deciding factor of the film growth mechanisms.

The sintering kinetics of samarium doped ceria (SDC) with addition of 5 mol% cobalt oxide is investigated by means of stepwise isothermal dilatometry (SID). We find that the isothermal shrinkage data from SID could be well analyzed to get kinetic parameters according to the empirical rate equation developed by Makipirtti–Meng, d ⁢ Y d ⁢ t = n ⁢ k ( T ) Y ( 1 − Y ) ( Y 1 − Y ) 1 n where Y is the fractional volume shrinkage during sintering process and n is a dimensionless exponent. The apparent activation energy ΔE values obtained for temperature ranges of 800–850 °C, 900–1000 °C and 1050–1150 °C are 66.4 kJ/mol, 467.7 kJ/mol and 71.8 kJ/mol, respectively. Correspondingly, the exponent n values for the three temperature ranges are also different. The mechanisms of the sintering process at various stages are discussed based on the parameters obtained associated with microstructure observation.

Chemical co-precipitation process and glycine-nitrate process (GNP) were used to synthesize (CeO2)0.8(Sm2O3)0.1(SDC) powders for the preparation of thin dense film by screen-printing. XRD, transmission electron microscope (TEM), scanning electron microscope (SEM) and the AC impedance spectroscopy were used to investigate the phase identification, morphology and electrical properties of SDC powders, respectively. It was found that the powders prepared by both processes possessed similar sinterability and conductivity. To both synthesized powders, the SDC pellets sintered at 1350 °C can reach 96% in relative density and 0.08 S cm−1 in conductivity at 800 °C in air. Thin electrolyte films about 30 μm have been successfully achieved by screen-printing with both powders. While the thin electrolyte film by GNP powders possessed better sinterability and higher conductivity, which was attributed to its high pack density during the green film preparation.

A novel aerosol-assisted metalorganic chemical vapor deposition (AA-MOCVD) technology was developed to prepare of Y2O3-stabilized ZrO2 (YSZ) thin films on polycrystalline substrates at the temperatures of 350–700 °C from metal β-diketonate chelates precursors. Thin films with rather uniform and amorphous microstructure were obtained at the substrate temperatures below 600 °C and changed into full cubic microstructure after annealing treatment at 1100 °C for 3 h. A detailed deposition mechanism has described the AA-MOCVD process. The resistance measurement of electrochemical cell Pt/Ni-YDC/YSZ film/Pt showed that conductivity activation energy (Ea) changed at 610 °C with 85.8 kJ/mol at 610–850 °C and 136 kJ/mol at 350–610 °C.

(CeO2)0.8(Sm2O3)0.2 (SDC) powders were prepared using the glycine–nitrate process (GNP) with different glycine/metal ratios. The phase identification, morphology and electrical properties of SDC powders were investigated by XRD, TEM and the AC impedance spectroscopy, respectively. It was found that the ratio of glycine/metal had a great effect on both the morphology and the sinterability of the powders as well as the conductivity of the sintered pellets. When the ratio is around the stoichiometric value (about 1.6), the loose powders possessed a foam-like structure. The bulk density of SDC pellets sintered at 1500 °C could reach 95% only when the ratio of glycine to metal was in the range of 1.3–2.0. The conductivity increased with the ratio of glycine to metal till at the ratio of 1.7, and then decreased. The maximum conductivity of the sintered specimens was 0.082 Scm−1 at 800 °C.

PVA films containing 12-tungstogermanic heteropoly acid have been successfully prepared for the first time. Infrared (IR) spectra revealed that the Keggin structure characteristic of the GeW 12 O 40 4− anion was present in the PVA films. The characteristic IR peaks have been identified and their change in wave number interpreted as a function of heteropoly acid (HPA) content. The film exhibited considerably high proton conductivity, which increased with the increase of the 12-tungstogermanic heteropoly acid content. At room temperature (20°C), the conductivity of the PVA film containing 80 wt.% 12-tungstogermanic heteropoly acid is 2.11×10 −2 S cm −1 . The photochromism of the PVA film was observed. Its color changed into blue.

La 1− x Sr x CoO 3 (LSC, x =0.10–0.50) powders with pure perovskite structure have been synthesized from mixtures of La 2 O 3 , SrCO 3 , and Co 3 O 4 , irradiated in a domestic microwave oven (DMO) with 2.4.5 GHz and 700–800 W output for no more than 25 min. It is found that Co 3 O 4 couples with microwave well and raises its temperature greatly within 3 min, while neither La 2 O 3 nor SrCO 3 absorbs microwave energy at the ordinary temperature. The microwave synthesizing conditions depend on the Sr 2+ replacement amount, and get difficult when x is high. The traditional solid state reaction method is compared to treat the same mixtures. It appears that the pure phases of LSC cannot be obtained until 1100–1200°C for 4 h. The lower temperature and shorter time with microwave irradiation might be ascribed to the activating and facilitating effect of microwave on solid phase diffusion. The LSC powders made by the microwave process were screen-printed onto compact yttrium-doped ceria (YDC) pellets, the common electrolyte for solid oxide fuel cells (SOFC), to observe the interaction between them. SEM photograph shows that LSC film has good sintering and porous properties, and fair compatibility with YDC. Thus, microwave irradiation is proved to be a novel, extremely facile, time-saving and energy-efficient route to the synthesis of LSC powders.

Nanoscale yttria doped ceria powder was successfully synthesized by azeotropic distillation process, which effectively dehydrated hydrous ceria and completely prevented the formation of hard agglomerates. After being calcined at 500°C for 2 h, the average powder size was less than 10 nm. Powder X-ray diffraction (XRD), transmission electron microscopy (TEM) and Raman spectroscopy were performed to characterize the powder properties. The electrical conductivity of the sintered pellets from this powder was also measured by a.c. impedance spectroscopy, with the values of 0.025 and 0.062 S cm −1 at 700°C and 800°C, respectively.

Gelcasting has been developed as a novel ceramic forming method for complex-shaped advanced materials of near-net-shape. In this work, the gelcasting process has been further developed to fabricate porous single- and multi-component ceramics. Porous multi-component ceramics were obtained from gelcast body of precursors by a reaction-sintering process. Large α-Al 2 O 3 powders with a d 50 value of 21.12 μm and mixed precursors were used to prepare porous α-Al 2 O 3 and La 0.6 Sr 0.4 Co 0.8 Fe 0.2 O 3− δ ceramics, respectively. The experimental results presented here demonstrate the utility of the gelcasting process for fabricating practically useful porous ceramics.

Perovskite-type LaFeO 3 has been synthesized hydrothermally under Na 2 CO 3 -containing medium, and characterized by X-ray diffraction (XRD), SEM, IR and ICP. The product corresponds to orthorhombic perovskite-type LaFeO 3 , with a cubic habit over a small particle size range of 10–20 μm. The LaFeO 3 formation temperature decreased by about 150°C by introducing carbonate into the hydrothermal system.

A new solid high-proton conductor molybdotungstovanadogermanic heteropoly acid H 5 GeW 9 Mo 2 VO 40 ·22H 2 O has been prepared for the first time by the stepwise acidification and the stepwise addition of solutions of the component elements. The product was characterized by chemical analysis, potentiometric titration, IR, UV, XRD and TG-DTA. The results of AC impedance measurement show that its proton conductivity at 18°C is 2.79×10 −4 S cm −1 and the activation energy for proton conduction is 35.64 kJ/mol.

Perovskite-type Ba 2 SbMO 6 (M=In, Y, Nd) oxides have been synthesized in Ba 2 O–Sb 2 O 5 –M 2 O 3 –K 2 O–H 2 O hydrothermal system. The synthesized Ba 2 SbMO 6 oxide powders were characterized by the techniques such as XRD, IR, SEM, XPS and ICP methods. The results indicated that the Ba/Sb/M ratio is very similar and closing to 2:1:1 in all the products, and the particle sizes of Ba 2 SbMO 6 oxides, where M=In, Y and Nd, are 1–2 μm, 0.5–1 μm and 0.5–2 μm, respectively.