Thermally-stable high dielectric properties of (1–x)(0.65Bi1.05FeO3–0.35BaTiO3)–xBiGaO3 piezoceramics

We report on a bottom-up manufacturing for high-k dielectric films using a novel nanomaterial, namely, a perovskite nanosheet (LaNb2O7) derived from a layered perovskite by exfoliation. Solution-based layer-by-layer assembly of perovskite nanosheets is effective for room-temperature fabrication of high-k nanocapacitors, which are directly assembled on a SrRuO3 bottom electrode with an atomically sharp interface. These nanocapacitors exhibit high dielectric constants (k > 50) for thickness down to 5 nm while eliminating problems resulting from the size effect. We also investigate dielectric properties of perovskite nanosheets with different compositions (LaNb2O7, La0.95Eu0.05Nb2O7, and Eu0.56Ta2O7) in order to study the influence of A- and B-site modifications on dielectric properties.

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Structure instability-induced high dielectric properties in [001]-oriented 0.68Pb(Mg1/3Nb2/3)O3–0.33PbTiO3 crystals

Chinese Physics B ◽

10.1088/1674-1056/28/5/057701 ◽

2019 ◽

Vol 28 (5) ◽

pp. 057701

Author(s):

Xiao-Juan Li ◽

Xing Fan ◽

Zeng-Zhe Xi ◽

Peng Liu ◽

Wei Long ◽

...

Keyword(s):

Dielectric Properties ◽

High Dielectric

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Fabrication of High Permittivity Resin Composite for Vat Photopolymerization 3D Printing: Morphology, Thermal, Dynamic Mechanical and Dielectric Properties

Materials ◽

10.3390/ma12233818 ◽

2019 ◽

Vol 12 (23) ◽

pp. 3818 ◽

Cited By ~ 5

Author(s):

Malas ◽

Isakov ◽

Couling ◽

Gibbons

Keyword(s):

Dielectric Properties ◽

3D Printing ◽

Resin Composite ◽

Ceramic Powder ◽

Reactive Polymer ◽

Calcium Copper Titanate ◽

Double Function ◽

High Dielectric ◽

Powder Content ◽

5 Ghz

The formulation of a high dielectric permittivity ceramic/polymer composite feedstock for daylight vat photopolymerization 3D printing (3DP) is demonstrated, targeting 3DP of devices for microwave and THz applications. The precursor is composed of a commercial visible light photo-reactive polymer (VIS-curable photopolymer) and dispersed titanium dioxide (TiO2, TO) ceramic nano-powder or calcium copper titanate (CCT) micro-powder. To provide consistent 3DP processing from the formulated feedstocks, the carefully chosen dispersant performed the double function of adjusting the overall viscosity of the photopolymer and provided good matrix-to-filler bonding. Depending on the ceramic powder content, the optimal viscosities for reproducible 3DP with resolution better than 100 µm were η(TO) = 1.20 ± 0.02 Pa.s and η (CCT) = 0.72 ± 0.05 Pa.s for 20% w/v TO/resin and 20% w/v CCT/resin composites at 0.1 s−1 respectively, thus showing a significant dependence of the “printability” on the dispersed particle sizes. The complex dielectric properties of the as-3D printed samples from pure commercial photopolymer and the bespoke ceramic/photopolymer mixes are investigated at 2.5 GHz, 5 GHz, and in the 12–18 GHz frequency range. The results show that the addition of 20% w/v of TO and CCT ceramic powder to the initial photopolymer increased the real part of the permittivity of the 3DP composites from ε’ = 2.7 ± 0.02 to ε’(TO) = 3.88 ± 0.02 and ε’(CCT) = 3.5 ± 0.02 respectively. The present work can be used as a guideline for high-resolution 3DP of structures possessing high-ε.

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Microstructure and Dielectric Properties of LixTixNi1-2xO Thin Films

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.368-372.1817 ◽

2008 ◽

Vol 368-372 ◽

pp. 1817-1819

Author(s):

Cui Hua Zhao ◽

Bo Ping Zhang ◽

Yong Liu ◽

Song Jie Li

Keyword(s):

Thin Films ◽

Dielectric Properties ◽

Spin Coating ◽

Sol Gel ◽

Dielectric Constants ◽

Co Doping ◽

Grain Sizes ◽

Uniform Microstructure ◽

Coating Method ◽

High Dielectric

LixTixNi1-2xO (x =0, 10 and 20 at. %) thin films with 200 nm in thickness were deposited on Pt/Ti/SiO2/Si (100) by a sol-gel spin-coating method. All samples have a uniform microstructure. The grain sizes grew from 100 nm to 300 nm by co-doping Li and Ti. The LiTiNiO thin films consist of NiO, NiTiO3 and Li2NiO2, while the Li-free thin films consist of NiO, NiTiO3 and NiTi0.99O3. The dielectric properties of the LiTiNiO thin films improved obviously by co-doping Li and Ti, but excess Li increases the amount of Li2NiO2 phase and decreases the dielectric properties. The dielectric constants at 100 Hz for the Li0.1Ti0.1Ni0.8O and Li0.2Ti0.2Ni0.6O thin films are 506 and 388 respectively. Appropriate co-doping contents of Li and Ti are important to obtain a high dielectric property.

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Structural, optical and microwave dielectric properties of Ba(Ti1−xSnx)4O9, 0 ≤ x ≤ 0.7 ceramics

Scientific Reports ◽

10.1038/s41598-021-97584-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Asad Ali ◽

Sarir Uddin ◽

Madan Lal ◽

Abid Zaman ◽

Zafar Iqbal ◽

...

Keyword(s):

Dielectric Properties ◽

Microwave Dielectric Properties ◽

Orthorhombic Symmetry ◽

X Ray Diffraction ◽

Low Dielectric ◽

Microwave Dielectric ◽

Ceramic Samples ◽

Red Color ◽

High Dielectric ◽

Quality Factor Q

AbstractSn-doped BaTi4O9 (BT4) dielectric ceramics were prepared by a mixed oxide route. Preliminary X-ray diffraction (XRD) structural study shows that the ceramic samples have orthorhombic symmetry with space group (Pnmm). Scanning electron microscopy (SEM) shows that the grain size of the samples decreases with an increase in Sn4+ content. The presence of the metal oxide efficient group was revealed by Fourier transform infrared (FTIR) spectroscopy. The photoluminescence spectra of the ceramic samples reported red color ~ 603, 604, 606.5 and 605 nm with excitation energy ~ 2.06, 2.05, 2.04 and 2.05 eV for Sn4+ content with x = 0.0, 0.3, 0.5, and 0.7, respectively. The microwave dielectric properties of these ceramic samples were investigated by an impedance analyzer. The excellent microwave dielectric properties i.e. high dielectric constant (εr = 57.29), high-quality factor (Qf = 11,852), or low-dielectric loss (3.007) has been observed.

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