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ZnNb2O6 ceramics with a columbite crystal structure, is a promising candidate for application in microwave devices. In this study, ZnNb2O6 nano-powders were prepared using Nb2O5 and Zn(NO3)2 as raw materials by Pechini method. The microstructure and crystal structure of ZnNb2O6 powders were investigated systematically using X-ray powder diffraction and SEM techniques. The effect of amount of citric and ethylene on the formation of sol-gel and the particle size of ZnNb2O6 powders were also investigated using orthogonal design. Finally, the optimum process parameters for synthesis ZnNb2O6 nano-powders were obtained in this study.

The effect of Fe2O3-TiO2 mixture additives on the crystallization behaviour of a parent glass with composition located in the primary field of cordierite within the MgO-Al2O3-SiO2 system has been examined. The crystallization behaviour of the glass was determined by differential thermal analysis (DTA) and X-ray diffraction (XRD). The microstructure was characterized by scanning electron microscopy (SEM). The results show that additives of Fe2O3-TiO2 can lower the temperature of the crystallization peak (Tp) and promote crystallization of the parent glass. By controlled thermal treatment, the main crystal phase obtained was Fe2+[removed info]substituted α-cordierite. The approach outlined in this paper to obtain heterogeneous ion substituted cordierite[removed info] glass-ceramics is useful to develop infrared radiation material with good properties.

ZrO2-TiO2 thin films, which were heat-treated with an applied electric field, were prepared by sol-gel method. The phase transformation behavior of ZrO2-TiO2 composite thin films was studied by DTA, XRD, SEM and Raman spectroscopy. In an electric field, the phase transformation temperature of amorphous phase to anatase and that of anatase to rutile are all decreased.