Polymorphic structure evolution and large piezoelectric response of lead-free (Ba,Ca)(Zr,Ti)O3 ceramics

Flexoelectricity describes the physical phenomenon of the generation of electric polarization from mechanical strain gradient in solid insulators. In common dielectric materials, the flexoelectric coefficient is trivially small ~10-10 C/m. In Ba(Sr,Ti)O 3 (BST) ceramics, flexoelectric coefficient up to 10-4 C/m was observed. Such high coefficient makes it possible to design high piezoelectric response flexoelectric composites. In this letter, we will demonstrate that the newly designed flexoelectric composites could have piezoelectric properties better than conventional piezoelectric materials.

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Hybrid Atmosphere Processing of Lead-Free Piezoelectric Sodium Potassium Niobate-Based Ceramics

Ceramics ◽

10.3390/ceramics2030035 ◽

2019 ◽

Vol 2 (3) ◽

pp. 460-471 ◽

Cited By ~ 2

Author(s):

Astri Bjørnetun Haugen

Keyword(s):

Lead Free ◽

Piezoelectric Response ◽

Potassium Niobate ◽

Sodium Potassium ◽

New Approach ◽

Sodium Potassium Niobate ◽

Phase Pure ◽

High Alkali ◽

Surface Decomposition ◽

Air Processing

K0.5Na0.5NbO3-based ceramics, a promising group of lead-free piezoelectrics, are challenging to sinter dense while avoiding alkali evaporation. This work explores hybrid atmosphere processing, a new approach where reducing atmospheres is used during heating to avoid coarsening from alkali carbonates and hydroxides, and oxidizing atmospheres is used during sintering to avoid alkali evaporation. Discs of Li0.06(K0.52Na0.48)0.94Nb0.71Ta0.29O3 with 0.25 mol% Mn (KNNLTM) were sintered in air, N2, 9% H2 in N2, or 9% H2 in N2 during heating and air during sintering (hybrid atmosphere processing). The highest density was obtained by sintering in 9% H2 in N2, but resulted in high alkali loss and decomposition of the surface, followed by low piezoelectric response. However, with the hybrid H2/air processing it was possible to both avoid surface decomposition and leakage currently associated with alkali evaporation during sintering in H2, and to obtain a denser, more phase-pure and small-grained KNNLTM ceramic with a higher piezoelectric response than obtained by sintering in air or N2.

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Structure evolution and exceptionally ultra-low hysteresis unipolar electric field-induced strain in (1−x)NaNbO3-xBaTiO3 lead-free ferroelectrics

Ceramics International ◽

10.1016/j.ceramint.2017.12.188 ◽

2018 ◽

Vol 44 (5) ◽

pp. 5492-5499 ◽

Cited By ~ 32

Author(s):

Xu Lu ◽

Lei Hou ◽

Li Jin ◽

Liang Wang ◽

Ye Tian ◽

...

Keyword(s):

Electric Field ◽

Lead Free ◽

Structure Evolution ◽

Electric Field Induced Strain

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Structure evolution and enhanced piezoelectric properties of (K0.5Na0.5)NbO3–0.06LiTaO3–SrZrO3 lead-free ceramics

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2015.09.055 ◽

2015 ◽

Vol 653 ◽

pp. 523-527 ◽

Cited By ~ 12

Author(s):

Xiaobin Yan ◽

Biaolin Peng ◽

Xuefeng Lu ◽

Qizheng Dong ◽

Wensheng Li

Keyword(s):

Piezoelectric Properties ◽

Lead Free ◽

Structure Evolution ◽

Lead Free Ceramics

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Polymorphic phase boundaries and enhanced piezoelectric response in extended composition range in the lead free ferroelectric BaTi1−xZrxO3

Journal of Applied Physics ◽

10.1063/1.4812472 ◽

2013 ◽

Vol 114 (1) ◽

pp. 014102 ◽

Cited By ~ 49

Author(s):

Ajay Kumar Kalyani ◽

Anatoliy Senyshyn ◽

Rajeev Ranjan

Keyword(s):

Composition Range ◽

Lead Free ◽

Piezoelectric Response ◽

Phase Boundaries

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Piezoelectric and Ferroelectric Properties of KNbO3 Added Bi0.5Na0.5TiO3 Ceramics

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.751.384 ◽

2017 ◽

Vol 751 ◽

pp. 384-389 ◽

Cited By ~ 2

Author(s):

Puripat Kantha ◽

Phathaitep Raksa ◽

Muangjai Unruan ◽

Tawee Tunkasiri ◽

Panupong Jaiban ◽

...

Keyword(s):

Mixed Oxide ◽

Room Temperature ◽

Ferroelectric Phase ◽

Ferroelectric Properties ◽

Lead Free ◽

Piezoelectric Response ◽

Rhombohedral Structure ◽

Rhombohedral Symmetry

The fabrication of lead-free (1-x)Bi0.5Na0.5TiO3 - xKNbO3 or (1-x)BNT-xKN ceramics where x = 0.00, 0.05, 0.10, and 0.15 was carried out by the modified two-step mixed oxide method. The effects of KNbO3 on structure, piezoelectric and ferroelectric properties were systematically investigated. XRD results revealed that the (1-x)BNT-xKN ceramics with low KN content of x less than 0.05 contained ferroelectric phase with a rhombohedral symmetry while the ceramics with x = 0.05 possessed pseudocubic structure. The higher KN content (x ≥ 0.10) ceramics had symmetries rhombohedral structure. At room temperature, the highest Pr and low Ec were obtained when the composition of x = 0.05. Moreover, the results showed the moderate KN addition could enhance the piezoelectric response. The d33 of 0.95BNT-0.05KN reached as high as 125 pC/N.

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Tetragonal BaTiO3 nanowires: a template-free salt-flux-assisted synthesis and its piezoelectric response based on mechanical energy harvesting

Journal of Materials Chemistry C ◽

10.1039/c9tc01622h ◽

2019 ◽

Vol 7 (27) ◽

pp. 8277-8286 ◽

Cited By ~ 7

Author(s):

Thitirat Charoonsuk ◽

Saichon Sriphan ◽

Chanisa Nawanil ◽

Narong Chanlek ◽

Wanwilai Vittayakorn ◽

...

Keyword(s):

Energy Harvesting ◽

High Performance ◽

Mechanical Energy ◽

Salt Flux ◽

Lead Free ◽

Piezoelectric Response ◽

Template Free

This research successfully demonstrated a facile, effective and scalable preparation of BaTiO3 nanowires (BT-NWs) via the template-free salt flux assisted method. High-performance lead-free flexible piezoelectric nanogenerator using BT-NWs was proposed in this work.

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