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Nanocomposites based on polyvinylidene fluoride– trifluoroethylene copolymer and up to 4 vol % of hydrophobized clay nanoparticles are investigated. The structure, piezoelectric properties, and oxygen permeability of solvent cast films are analyzed before ...
Defect engineering is one of the cornerstones of the modern electronics industry. Almost all electronic devices include materials that have been doped by ion bombardment. For materials where crystallinity is essential, such as ferroelectrics, defect type a ...
Copolymer nanoparticles with a highly polar repeating unit are blended in an elastic matrix and poled at elevated temperatures. The composite exhibits piezoelectricity due to the overall polarization imparted by the particles, which can be easily modulated ...
The high Curie temperature (T-C similar to 825 degrees C) of BiFeO3 has made this material potentially attractive for the development of high-T-C piezoelectric ceramics. Despite significant advances in the search of new BiFeO3-based compositions, the piezo ...
Piezoelectricity describes interconversion between electrical charge and mechanical strain. As expected for lattice ions displaced in an electric field, the proportionality constant is positive for all piezoelectric materials. The exceptions are poly(vinyl ...
Mobile charged defects, accumulated in the domain-wall region to screen polarization charges, have been proposed as the origin of the electrical conductivity at domain walls in ferroelectric materials. Despite theoretical and experimental efforts, this sce ...
The dynamic dielectric nonlinearity of barium strontium titanate (Ba1-x, Sr-x) TiO3 ceramics is investigated in their paraelectric phase. With the goal to contribute to the identification of the mechanisms that govern the dielectric nonlinearity in this fa ...
Bismuth ferrite (BiFeO3) is difficult to pole because of the combination of its high coercive field and high electrical conductivity. This problem is particularly pronounced in thick films. The poling, however, must be performed to achieve a large macrosco ...
The results of recent studies of domain walls and their interaction with defects in BaTiO3, Pb(Zr, Ti)O-3, and BiFeO3 are discussed. The studies reveal why donor- and acceptor-doped Pb(Zr, Ti)O-3 behave differently, what is the role of stationary charged d ...
BaTiO3 appears in cubic and hexagonal variants, both of which are centrosymmetric. Samples of cubic BaTiO3 are known to exhibit breaking of the centric symmetry locally and globally. It has been proposed that the local symmetry breaking originates in polar ...
