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Nanocrystalline Ba1−xSrxTiO3 (x=0, 0.2, 0.4, 0.6, 0.8 and 1.0) precursors were synthesized using the stearic acid gel method. After the precursors had been calcined at 600–950°C for 0.5–1 h, nanocrystalline powders with the cubic perovskite structure were obtained and these were made into thick films. The powder samples were characterized by differential thermal analysis, X-ray diffraction and transmission electron microscopy, and the thick film samples were characterized by scanning electron microscopy and X-ray diffraction. The humidity-sensitive properties of the nanocrystalline Ba1−xSrxTiO3 thick films were investigated. The results show that these nanocrystalline thick films possess higher humidity sensitivity and lower resistance than those of conventional materials.

Raman spectra of nanocrystalline LaFeO 3 ,La 1 − x Sr x FeO 3 ( x = 0.1, 0.2, 0.4),LaCoO 3 ,La 0.8 Sr 0.2 CoO 3 ,La 0.8 Sr 0.2 Fe 0.4 Co 0.6 O 3 and Bi 2 Ti 4 O 11 materials were examined under compacting pressures of 0.0,0.5,1.0 and 1.5 GPa (0.0–13.0 GPa for Bi 2 Ti 4 O 11 ). The results indicate that the Raman spectra of the samples change with grain size, components and compacting pressure. After nanocrystalline LaCoO 3 and La 0.8 Sr 0.2 CrO 3 samples had been left in situ for 48 h at room temperature, the shape of the Raman bands had changed

Electron paramagnetic resonance (EPR) spectroscopy was used to study nanocrystalline La1 − xSrxFe1 − yCo yO3 samples. Nanocrystalline powders were compacted into nanocrystalline solid materials under compacting pressures of 0.5, 1.0 and 1.5 GPa in the axial direction at ambient temperature. The results show that the EPR spectra of the samples change with the grain sizes, compacting pressure and components, and their g values change with the increment of the compacting pressure, whereas the relative intensities of the EPR spectra of nanocrystalline materials are about 102–103 times as strong as those of conventional materials.