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Bismuth-layer-structured (Ba 1−xMn x)Bi 4Ti 4O 15 (0.0 ≤  x ≤ 0.8) ceramics were prepared by a Sol–Gel method. The effects of the amount of Mn-doped on the phase structure, the dielectric as well as piezoelectric properties of BaBi 4Ti 4O 15 ceramics were studied. The X-ray diffraction results revealed that the introduction of Mn resulting in distortion of lattice, which contributes to the crystallization of the layered structure grains. The densification, dielectric and piezoelectric properties of the (Ba 1−xMn x)Bi 4Ti 4O 15 ceramics were significantly promoted by the Mn substitution of Ba. When the value of doping amount Mn is 0.4, the (Ba 0.6Mn 0.4)Bi 4Ti 4O 15 ceramic exhibited a high piezoelectric constant ( d33 = 7.5 pC/N), a big relatively dielectric constant ( εr = 764.26) and a small dielectric loss (tan δ = 0.0124). [ABSTRACT FROM AUTHOR]

Lanthanum strontium ferrite (La 1−xSr xFeO 3, x = 0.1, 0.3, 0.5, 0.7) (LSF) films were prepared on platinized/silica/silicon (Pt/SiO 2/Si) substrates by a sol–gel method. The crystallization, surface morphology and dielectric properties of the LSF films have been studied. Among the samples, La 0.5Sr 0.5FeO 3 thin film have the most homogeneous, smooth surface and the best dielectric properties ( εr = 2881.58, tanδ = 1.20) at the frequency of 1 kHz. Mn-doping ( y) in La 0.5Sr 0.5FeO 3 further improves the dielectric properties ( εr = 2922.91, tanδ = 1.11) of the film. Both εr and tanδ values of the Mn-doped ( y = 0.02) La 0.5Sr 0.5FeO 3 films decreases with increasing the frequency. The biggest εr value is 3238.18 at the frequence of 0.02 kHz. [ABSTRACT FROM AUTHOR]