Dark Self-Healing-Mediated Negative Photoconductivity of a Lead-Free Cs3Bi2Cl9 Perovskite Single Crystal

Langasite (La3Ga5SiO14: denoted by LGS) single crystal is one of the lead free piezoelectric materials with high piezoelectricity that is maintained up to its melting point (1470°C). Although LGS single crystals have usually been grown by Czochralski (CZ) method in oxygen contained atmosphere to prevent evaporation of Ga, they were grown by the vertical Bridgman (VB) method in Ar atmosphere without oxygen, and their properties were evaluated in this work. Transparent and colorless LGS single crystals were successfully obtained without Ga evaporation by the VB method in Ar atmosphere, and their resistivity at room temperature was much higher than that grown by conventional CZ method. Piezoelectric constant d11 of the crystal grown by the VB method was 6 x 10-12 C/N, which was close to that of the crystal grown by CZ method. The colorless transparent LGS single crystal turned to orange and its resistivity decreased by annealing in air. Since an orange-colored transparent LGS single crystal has been grown by conventional CZ method, this indicates that color change and the resistivity decrease of LGS crystal is caused by extra interstitial oxygen atoms in the crystal.

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Centimeter-Sized Single Crystal of a One-Dimensional Lead-Free Mixed-Cation Perovskite Ferroelectric for Highly Polarization Sensitive Photodetection

Journal of the American Chemical Society ◽

10.1021/jacs.1c08281 ◽

2021 ◽

Vol 143 (40) ◽

pp. 16758-16767

Author(s):

Weichuan Zhang ◽

Maochun Hong ◽

Junhua Luo

Keyword(s):

Single Crystal ◽

Lead Free ◽

One Dimensional ◽

Mixed Cation

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Comparative study on the performance of piezo-active 1–3-type composites with lead-free components

Journal of Advanced Dielectrics ◽

10.1142/s2010135x21600031 ◽

2021 ◽

pp. 2160003

Author(s):

Ashura N. Isaeva ◽

Vitaly Yu. Topolov

Keyword(s):

Single Crystal ◽

Piezoelectric Coefficient ◽

Piezoelectric Properties ◽

Volume Fraction ◽

Lead Free ◽

Figures Of Merit ◽

Piezoelectric Energy ◽

Harvesting Systems ◽

Porous Matrices ◽

Large Anisotropy

Piezoelectric properties and related figures of merit are studied in novel 1–3-type composites based on ferroelectric domain-engineered lead-free single crystal with the relatively large longitudinal piezoelectric coefficient [Formula: see text]. Relationships between the piezoelectric properties and the set of figures of merit are analyzed for the 1–3 and 1–3–0 composites that contain the same single-crystal and polymer components. For a composite characterized by 1–3–0 connectivity, an influence of a porous piezo-passive matrix on the figures of merit and their volume-fraction behavior is considered additionally. A large anisotropy of figures of merit is observed in the 1–3–0 composite with specific porous matrices. A diagram is put forward to show volume-fraction regions of the large anisotropy of figures of merit of the studied 1–3–0 composite. Due to large figures of merit and their considerable anisotropy, the studied lead-free composites can be applied in piezoelectric energy-harvesting systems, sensors, transducers, and so on.

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Enhanced fatigue resistance and lattice dynamics induced by the strong local strain in Fe-doped KTa1-xNbxO3 single crystal

Journal of Materials Chemistry C ◽

10.1039/d1tc04480j ◽

2021 ◽

Author(s):

Xiaolin Huang ◽

Peng Tan ◽

Yu Wang ◽

Yao Zhang ◽

Xiangda Meng ◽

...

Keyword(s):

Single Crystal ◽

Fatigue Resistance ◽

Lattice Dynamics ◽

Piezoelectric Materials ◽

Local Strain ◽

Lead Free ◽

Fatigue Properties ◽

Practical Applications ◽

Local Structures ◽

The Impact

Improvement of durability is greatly important for the practical applications of lead-free-doped piezoelectric materials. However, the promotional mechanism of anti-fatigue properties and the impact on local structures from ion dopants...

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