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The influence of heat treatment and substrate materials on PLT thin films by sol-gel processing has been researched. Epitaxial growth PLT thin films with perovskite-type structure on sapphire, SrTiO3 and MgO single crystal substrates have been prepared. The epitaxial relations are (100)PLT28/(100)SrTiO3, (111)PLT28//(0001)sapphire and (100)PLT14//(100)MgO. The PLT polycrystal thin films with perovskite-type structure on Si single crystal and quartz glass substrates have been prepared. The remanent polarization Pr and the coercive field Ec of PLT15 ceramic thin films are 7.7 μc/cm2 and 34 kv/cm at 4 KHz respectively. The optical transmittance of PLT28 ceramic thin films within the wavelength range of λ = 500–1000 nm is approximately 80%.

PbTiO 3 polycrystalline thin films with perovskite structure have been prepared on an Si single-crystal substrate by sol-gel processing. Highly oriented perovskite PbTiO 3 thin films have also been prepared on MgO and SrTiO 3 single-crystal substrates. The PbTiO 3 thin films have good ferroelectricity and pyroelectricity. The values of spontaneous polarization P s , remanent polarization P r and coercive field E c of the PbTiO 3 polycrystalline thin films are 30 μC/cm 2 , 15 μC/cm 2 and 50 kV/cm, respectively. The polycrystalline thin films have a high pyroelectric coefficient γ of 2.9 × 10 −8 C/cm 2 K, high figure of merit for voltage responsivity F v (=γ/ C v e r ) of 60 × 10 −12 C cm/J and a figure of merit for specific detectivity F m (=γ/ C v (e r tg δ) 1/2 ) of 0.74 × 10 −8 C cm/J.

Barium titanate gels were prepared from barium acetate and tetrabutyl titanate by sol-gel processing. The results of DTA and XRD showed that as-prepared gels were transformed into crystalline with tetragonal ferroelectric phase by a heat treatment at 600°C. It was found that soaking the BaTiO3 crystalline powders in nitric acid could increase the density of the ceramic bodies. The density of the resultant bodies is near 96% of the theoretical value. The dielectric measurement on most of the ceramic bodies showed that the magnitude of dielectric constant is 16,000 at its peak and 2500 at room temperature. D-E hysteresis loop was observed.

Ni64B36 glass has been investigated by X-ray diffraction, and conventional and pulse neutron diffraction, and evidence of first neighbour boron-boron atoms has been obtained.