---
_id: '9866'
abstract:
- lang: eng
  text: The hydrothermal method utilizes a solution-based chemical reaction to synthesize
    piezoelectric thin films and powders. This method has a number of advantages,
    such as low-temperature synthesis, and high purity and high quality of the product.
    In order to promote hydrothermal reactions, we developed an ultrasonic assisted
    hydrothermal method and confirmed that it produces dense and thick lead--zirconate--titanate
    (PZT) films. In the hydrothermal method, a crystal growth process follows the
    nucleation process. In this study, we verified that ultrasonic irradiation is
    effective for the nucleation process, and there is an optimum irradiation period
    to obtain thicker PZT films. With this optimization, a 9.2-$\mu$ m-thick PZT polycrystalline
    film was obtained in a single deposition process. For this film, ultrasonic irradiation
    was carried out from the beginning of the reaction for 18 h, followed by a 6 h
    deposition without ultrasonic irradiation. These results indicate that the ultrasonic
    irradiation mainly promotes the nucleation process.
author:
- first_name: Kanako
  full_name: Ohta, Kanako
  last_name: Ohta
- first_name: Gaku
  full_name: Isobe, Gaku
  last_name: Isobe
- first_name: Peter
  full_name: Bornmann, Peter
  last_name: Bornmann
- first_name: Tobias
  full_name: Hemsel, Tobias
  id: '210'
  last_name: Hemsel
- first_name: Takeshi
  full_name: Morita, Takeshi
  last_name: Morita
citation:
  ama: Ohta K, Isobe G, Bornmann P, Hemsel T, Morita T. Study on optimizing ultrasonic
    irradiation period for thick polycrystalline PZT film by hydrothermal method.
    <i>Ultrasonics</i>. 2013;53(4):837-841. doi:<a href="https://doi.org/10.1016/j.ultras.2012.12.003">10.1016/j.ultras.2012.12.003</a>
  apa: Ohta, K., Isobe, G., Bornmann, P., Hemsel, T., &#38; Morita, T. (2013). Study
    on optimizing ultrasonic irradiation period for thick polycrystalline PZT film
    by hydrothermal method. <i>Ultrasonics</i>, <i>53</i>(4), 837–841. <a href="https://doi.org/10.1016/j.ultras.2012.12.003">https://doi.org/10.1016/j.ultras.2012.12.003</a>
  bibtex: '@article{Ohta_Isobe_Bornmann_Hemsel_Morita_2013, title={Study on optimizing
    ultrasonic irradiation period for thick polycrystalline PZT film by hydrothermal
    method}, volume={53}, DOI={<a href="https://doi.org/10.1016/j.ultras.2012.12.003">10.1016/j.ultras.2012.12.003</a>},
    number={4}, journal={Ultrasonics}, author={Ohta, Kanako and Isobe, Gaku and Bornmann,
    Peter and Hemsel, Tobias and Morita, Takeshi}, year={2013}, pages={837–841} }'
  chicago: 'Ohta, Kanako, Gaku Isobe, Peter Bornmann, Tobias Hemsel, and Takeshi Morita.
    “Study on Optimizing Ultrasonic Irradiation Period for Thick Polycrystalline PZT
    Film by Hydrothermal Method.” <i>Ultrasonics</i> 53, no. 4 (2013): 837–41. <a
    href="https://doi.org/10.1016/j.ultras.2012.12.003">https://doi.org/10.1016/j.ultras.2012.12.003</a>.'
  ieee: K. Ohta, G. Isobe, P. Bornmann, T. Hemsel, and T. Morita, “Study on optimizing
    ultrasonic irradiation period for thick polycrystalline PZT film by hydrothermal
    method,” <i>Ultrasonics</i>, vol. 53, no. 4, pp. 837–841, 2013.
  mla: Ohta, Kanako, et al. “Study on Optimizing Ultrasonic Irradiation Period for
    Thick Polycrystalline PZT Film by Hydrothermal Method.” <i>Ultrasonics</i>, vol.
    53, no. 4, 2013, pp. 837–41, doi:<a href="https://doi.org/10.1016/j.ultras.2012.12.003">10.1016/j.ultras.2012.12.003</a>.
  short: K. Ohta, G. Isobe, P. Bornmann, T. Hemsel, T. Morita, Ultrasonics 53 (2013)
    837–841.
date_created: 2019-05-20T12:03:07Z
date_updated: 2019-09-16T10:54:27Z
department:
- _id: '151'
doi: 10.1016/j.ultras.2012.12.003
intvolume: '        53'
issue: '4'
keyword:
- Piezoelectric material
language:
- iso: eng
page: 837 - 841
publication: Ultrasonics
publication_identifier:
  issn:
  - 0041-624X
quality_controlled: '1'
status: public
title: Study on optimizing ultrasonic irradiation period for thick polycrystalline
  PZT film by hydrothermal method
type: journal_article
user_id: '55222'
volume: 53
year: '2013'
...
---
_id: '9758'
abstract:
- lang: eng
  text: As a lead-free piezoelectric ceramics, (K,Na)NbO$_{3}$ is a promising material
    because of its good piezoelectric properties. In this study, (K$_{1-x}$Na$_{x}$)NbO$_{3}$
    ceramics were synthesized from a KNbO$_{3}$ and NaNbO$_{3}$ mixture powder prepared
    by the hydrothermal reaction. The hydrothermal reaction enables the production
    of high quality powder for the ceramics fabrication process. To obtain (K$_{1-x}$Na$_{x}$)NbO$_{3}$
    ceramics, these two powders KNbO$_{3}$ and NaNbO$_{3}$ were mixed and then sintered
    together. X-Ray diffraction analysis revealed that the solid solution ceramics
    (K$_{1-x}$Na$_{x}$)NbO$_{3}$ was produced by the sintering process. The K/Na ratio
    in (K$_{1-x}$Na$_{x}$)NbO$_{3}$ ceramics was optimized for the best piezoelectric
    properties. The optimized forms was (K$_{0.48}$Na$_{0.52}$)NbO$_{3}$, which showed
    the following piezoelectric properties; k$_{33}$=0.56, d$_{33}$=114pC/N. In addition,
    the ferroelectric properties, P$_{r}$=7.72mC/cm$^{2}$, E$_{c}$=857V/mm, and the
    Curie temperature T$_{c}$=420$_{o}$C were also measured.
author:
- first_name: Takafumi
  full_name: Maeda, Takafumi
  last_name: Maeda
- first_name: Norihito
  full_name: Takiguchi, Norihito
  last_name: Takiguchi
- first_name: Takeshi
  full_name: Morita, Takeshi
  last_name: Morita
- first_name: Mutsuo
  full_name: Ishikawa, Mutsuo
  last_name: Ishikawa
- first_name: Tobias
  full_name: Hemsel, Tobias
  id: '210'
  last_name: Hemsel
citation:
  ama: Maeda T, Takiguchi N, Morita T, Ishikawa M, Hemsel T. Hydrothermal (K1-xNax)NbO3
    Lead-free Piezoelectric Ceramics. <i>Journal of Korean Physical Society</i>. 2010;57(4):924-928.
    doi:<a href="https://doi.org/10.3938/jkps.57.924">10.3938/jkps.57.924</a>
  apa: Maeda, T., Takiguchi, N., Morita, T., Ishikawa, M., &#38; Hemsel, T. (2010).
    Hydrothermal (K1-xNax)NbO3 Lead-free Piezoelectric Ceramics. <i>Journal of Korean
    Physical Society</i>, <i>57</i>(4), 924–928. <a href="https://doi.org/10.3938/jkps.57.924">https://doi.org/10.3938/jkps.57.924</a>
  bibtex: '@article{Maeda_Takiguchi_Morita_Ishikawa_Hemsel_2010, title={Hydrothermal
    (K1-xNax)NbO3 Lead-free Piezoelectric Ceramics}, volume={57}, DOI={<a href="https://doi.org/10.3938/jkps.57.924">10.3938/jkps.57.924</a>},
    number={4}, journal={Journal of Korean Physical Society}, author={Maeda, Takafumi
    and Takiguchi, Norihito and Morita, Takeshi and Ishikawa, Mutsuo and Hemsel, Tobias},
    year={2010}, pages={924–928} }'
  chicago: 'Maeda, Takafumi, Norihito Takiguchi, Takeshi Morita, Mutsuo Ishikawa,
    and Tobias Hemsel. “Hydrothermal (K1-XNax)NbO3 Lead-Free Piezoelectric Ceramics.”
    <i>Journal of Korean Physical Society</i> 57, no. 4 (2010): 924–28. <a href="https://doi.org/10.3938/jkps.57.924">https://doi.org/10.3938/jkps.57.924</a>.'
  ieee: T. Maeda, N. Takiguchi, T. Morita, M. Ishikawa, and T. Hemsel, “Hydrothermal
    (K1-xNax)NbO3 Lead-free Piezoelectric Ceramics,” <i>Journal of Korean Physical
    Society</i>, vol. 57, no. 4, pp. 924–928, 2010.
  mla: Maeda, Takafumi, et al. “Hydrothermal (K1-XNax)NbO3 Lead-Free Piezoelectric
    Ceramics.” <i>Journal of Korean Physical Society</i>, vol. 57, no. 4, 2010, pp.
    924–28, doi:<a href="https://doi.org/10.3938/jkps.57.924">10.3938/jkps.57.924</a>.
  short: T. Maeda, N. Takiguchi, T. Morita, M. Ishikawa, T. Hemsel, Journal of Korean
    Physical Society 57 (2010) 924–928.
date_created: 2019-05-13T10:19:43Z
date_updated: 2022-01-06T07:04:19Z
department:
- _id: '151'
doi: 10.3938/jkps.57.924
intvolume: '        57'
issue: '4'
keyword:
- Lead-free piezoelectric material
- KNN
- Hydrothermal method
language:
- iso: eng
page: 924-928
publication: Journal of Korean Physical Society
publication_identifier:
  issn:
  - 1948-5719
quality_controlled: '1'
status: public
title: Hydrothermal (K1-xNax)NbO3 Lead-free Piezoelectric Ceramics
type: journal_article
user_id: '55222'
volume: 57
year: '2010'
...
---
_id: '9759'
abstract:
- lang: eng
  text: Among various lead-free piezoelectric materials, (K,Na)NbO$_{3}$ is a very
    promising candidate. In this study, (K,Na)NbO$_{3}$ ceramics were sintered from
    mixed (K,Na)NbO$_{3}$ and NaNbO$_{3}$ powders prepared by hydrothermal reaction.
    These two powders were mixed with distilled water in a KNbO$_{3}$/NaNbO$_{3}$
    molar ratio of 1. After sintering the mixed powder, the solid solution of (Na,K)NbO$_{3}$
    ceramics was obtained. The electrical properties such as the electromechanical
    coupling factors k$_{p}$ and k$_{33}$, the mechanical quality factor, Q$_{m}$,
    and the piezoelectric constant d$_{33}$ of the sintered (K,Na)NbO$_{3}$ ceramics
    were 0.32, 0.48, 71 (radial mode), 118 ((33)mode), and 107 pC/N, respectively.
author:
- first_name: Takafumi
  full_name: Maeda, Takafumi
  last_name: Maeda
- first_name: Norihito
  full_name: Takiguchi, Norihito
  last_name: Takiguchi
- first_name: Takeshi
  full_name: Morita, Takeshi
  last_name: Morita
- first_name: Mutsuo
  full_name: Ishikawa, Mutsuo
  last_name: Ishikawa
- first_name: Tobias
  full_name: Hemsel, Tobias
  id: '210'
  last_name: Hemsel
citation:
  ama: Maeda T, Takiguchi N, Morita T, Ishikawa M, Hemsel T. (K,Na)NbO3 lead-free
    piezoelectric ceramics synthesized from hydrothermal powders. <i>Materials Letters</i>.
    2010;64(2):125-128. doi:<a href="https://doi.org/10.1016/j.matlet.2009.10.012">10.1016/j.matlet.2009.10.012</a>
  apa: Maeda, T., Takiguchi, N., Morita, T., Ishikawa, M., &#38; Hemsel, T. (2010).
    (K,Na)NbO3 lead-free piezoelectric ceramics synthesized from hydrothermal powders.
    <i>Materials Letters</i>, <i>64</i>(2), 125–128. <a href="https://doi.org/10.1016/j.matlet.2009.10.012">https://doi.org/10.1016/j.matlet.2009.10.012</a>
  bibtex: '@article{Maeda_Takiguchi_Morita_Ishikawa_Hemsel_2010, title={(K,Na)NbO3
    lead-free piezoelectric ceramics synthesized from hydrothermal powders}, volume={64},
    DOI={<a href="https://doi.org/10.1016/j.matlet.2009.10.012">10.1016/j.matlet.2009.10.012</a>},
    number={2}, journal={Materials Letters}, author={Maeda, Takafumi and Takiguchi,
    Norihito and Morita, Takeshi and Ishikawa, Mutsuo and Hemsel, Tobias}, year={2010},
    pages={125–128} }'
  chicago: 'Maeda, Takafumi, Norihito Takiguchi, Takeshi Morita, Mutsuo Ishikawa,
    and Tobias Hemsel. “(K,Na)NbO3 Lead-Free Piezoelectric Ceramics Synthesized from
    Hydrothermal Powders.” <i>Materials Letters</i> 64, no. 2 (2010): 125–28. <a href="https://doi.org/10.1016/j.matlet.2009.10.012">https://doi.org/10.1016/j.matlet.2009.10.012</a>.'
  ieee: T. Maeda, N. Takiguchi, T. Morita, M. Ishikawa, and T. Hemsel, “(K,Na)NbO3
    lead-free piezoelectric ceramics synthesized from hydrothermal powders,” <i>Materials
    Letters</i>, vol. 64, no. 2, pp. 125–128, 2010.
  mla: Maeda, Takafumi, et al. “(K,Na)NbO3 Lead-Free Piezoelectric Ceramics Synthesized
    from Hydrothermal Powders.” <i>Materials Letters</i>, vol. 64, no. 2, 2010, pp.
    125–28, doi:<a href="https://doi.org/10.1016/j.matlet.2009.10.012">10.1016/j.matlet.2009.10.012</a>.
  short: T. Maeda, N. Takiguchi, T. Morita, M. Ishikawa, T. Hemsel, Materials Letters
    64 (2010) 125–128.
date_created: 2019-05-13T10:21:17Z
date_updated: 2022-01-06T07:04:19Z
department:
- _id: '151'
doi: 10.1016/j.matlet.2009.10.012
intvolume: '        64'
issue: '2'
keyword:
- Lead-free piezoelectric material
- (K
- Na)NbO$_{3}$ ceramics
- Sintering solid solution
- Piezoelectric properties
language:
- iso: eng
page: 125-128
publication: Materials Letters
publication_identifier:
  issn:
  - 1948-5719
quality_controlled: '1'
status: public
title: (K,Na)NbO3 lead-free piezoelectric ceramics synthesized from hydrothermal powders
type: journal_article
user_id: '55222'
volume: 64
year: '2010'
...