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Antiferroelectric thin films have attracted blooming interest due to their potential application in energy storage areas. Pb(1−3x/2)LaxHfO3 (PLHO-x, x = 0–0.05) thin films were fabricated on Pt(111)/TiO2/SiO2/Si substrates via the chemical solution deposition method. The x-ray diffraction and high-resolution transmission electron microscopy results show that the doping of La3+, which has a smaller ion radius, leads to a slight decrease in the lattice constant and unit cell volume, which can induce the lattice distortion. In addition, the dielectric and polarization properties indicate that with an increase in the temperature or La3+ content, the antiferroelectric (AFE) I phase can transform into an AFE II phase, exhibiting a slimmer P–E loop with enhanced switching field and more pronounced polarization dispersion. Notably, PLHO-0.04 showcases excellent energy storage performance (55 J/cm3, at 2.8 MV/cm). This material also exhibits good thermal, frequency, and fatigue stability. These results suggest that the energy storage performance of PbHfO3-based films can be enhanced through the phase structure design, presenting a valuable approach to fulfill the growing demand for advanced energy storage devices. [ABSTRACT FROM AUTHOR]

Compared to the bulky ceramic counterparts, antiferroelectric (AFE) thin films exhibit higher energy-storage performance. It has been demonstrated that the performance of the AFE thin films is strongly affected by the thickness. However, possible changes in the phase structures and microstructures accompanied by varying thicknesses have been less known, which makes it hard to fully understand the physical insight of the thickness effect. Herein, we fabricate a series of PbZrO3 (PZ) thin films by chemical solution deposition whose thickness is approximately proportional to the number of deposition layers, i.e., one to four layers with each layer of about 60 nm in thickness. The detailed structural characterization has been performed by using x-ray diffraction, a scanning electron microscope, and a transmission electron microscope. The films are composed of nanorods oriented normal to the films in which each nanorod maintains single crystalline though segmented by the horizontal interfaces between each of the two neighboring layers, suggesting nearly perfect epitaxy during multilayer growth. The multidomain state is found in three-/four-layer PZ thin films while the one-/two-layer PZ films always present a monodomain state. Meanwhile, incommensurate phases with different modulation periods have been observed in the four-layer PZ films. By comparing the as-observed structural features with the measured electrical properties of different films, it seems that microstructural evolution with the film thickness should not be negligible in evaluating the structure–property relation of PZ-based thin films. [ABSTRACT FROM AUTHOR]

Utilizing temperature and magnetic field dependent dielectric spectroscopy, two different dielectric relaxation processes, both accompanied with prominent positive magnetodielectric (MD) effects, were observed in Pt/BiScO3-PbTiO3/La0.7Sr0.3MnO3 (Pt/BSPT/LSMO) heterostructure. An equivalent circuit model is established to quantitatively describe the relaxation data well. The simulation results elucidated that one relaxation process can be attributed to magnetic order associated BSPT/LSMO interfacial relaxation with abnormal dynamics feature. Another one is due to the external contact interface contributions. Both relaxation dynamics can be tuned, via magnetic field controlled localization of free interfacial charges, to induce MD effects in BSPT/LSMO interfaces and nonmagnetic Pt/BSPT contacts. [ABSTRACT FROM AUTHOR]

Using spectroscopic ellipsometry, the optical properties of the Bi[sub 3.25]La[sub 0.75]Ti[sub 3]O[sub 12] (BLT) thin films with different film thicknesses on platinized silicon substrates prepared by chemical solution methods have been investigated in the 400-1700 nm wavelength range. By fitting the measured ellipsometric parameter (ψ and Δ) data with a multilayer model system and the classical dispersion relation for the BLT thin films, the optical constants and thicknesses of the thin films have been obtained. Meanwhile, some degree of inhomogeneity (in the form of low density layers or surface roughness) has been found in the BLT thin films except for the thinnest film, which was homogeneous throughout its thickness. The multilayer model system became very complicated with increasing thickness. It indicated that the microstructure of the BLT thin films varied with increasing thickness. The refractive index n of the BLT thin films increases with increasing thickness, and on the contrary, the extinction coefficient k decreases with increasing thickness. The dispersion of the refractive index can be well explained by a single-term Sellmeier relation. [ABSTRACT FROM AUTHOR]