Projects / Programmes
High-performance piezoelectric materials for sensors and actuators in high-temperature applications
| Code |
Science |
Field |
Subfield |
| 2.09.01 |
Engineering sciences and technologies |
Electronic components and technologies |
Materials for electronic components |
| Code |
Science |
Field |
| T153 |
Technological sciences |
Ceramic materials and powders |
| Code |
Science |
Field |
| 2.05 |
Engineering and Technology |
Materials engineering |
high-temperature piezoelectric ceramics, BiFeO3, sensors, actuators.
Researchers (10)
| no. |
Code |
Name and surname |
Research area |
Role |
Period |
No. of publicationsNo. of publications |
| 1. |
08346 |
Darko Belavič |
Electronic components and technologies |
Researcher |
2013 - 2016 |
682 |
| 2. |
19038 |
PhD Andreja Benčan Golob |
Materials science and technology |
Researcher |
2013 - 2016 |
528 |
| 3. |
14390 |
Marjan Hodnik |
Electronic components and technologies |
Researcher |
2015 - 2016 |
27 |
| 4. |
30036 |
Brigita Kmet |
|
Technical associate |
2013 - 2016 |
168 |
| 5. |
04587 |
PhD Barbara Malič |
Electronic components and technologies |
Researcher |
2013 - 2016 |
1,479 |
| 6. |
33277 |
PhD Jernej Pavlič |
Electronic components and technologies |
Junior researcher |
2013 - 2014 |
37 |
| 7. |
24272 |
PhD Tadej Rojac |
Electronic components and technologies |
Head |
2013 - 2016 |
595 |
| 8. |
27820 |
Tina Ručigaj Korošec |
|
Technical associate |
2013 - 2016 |
0 |
| 9. |
04378 |
PhD Marina Santo Zarnik |
Electronic components and technologies |
Researcher |
2013 - 2016 |
374 |
| 10. |
37130 |
PhD Julian Bradley Walker |
Electronic components and technologies |
Researcher |
2015 |
91 |
Organisations (2)
Abstract
Piezoelectric components and devices are playing an important role in electronics and microsystems. The unique multifunctionality of the piezoelectric materials, from which these components and devices are made of, provides a route to many new future applications where inter-conversions between mechanical, thermal and electrical variables are needed.
Over 50 years, one piezoelectric material has been dominating the market, that is lead-zirconate titanate or Pb(Zr,Ti)O3 (PZT). What makes this material exceptional is its excellent electro-mechanical activity and adaptability for many different piezoelectric applications. There are two major reasons why this material should be replaced. The first is related to its chemical compositions. PZT contains a large amount of toxic lead and was recently included in the European Union (EU) legislature to be replaced by environmentally safer materials [1]. Secondly, many existing piezoelectric applications and demands for new products require operating conditions, such as high temperatures (above 200°C), that surpass the capability of PZT. There are many different areas demanding for high-temperature operating conditions in a range not covered by the market-leading PZT-based materials, including automotive industry, energy production, aerospace, medical field and microelectronics. PZT with the morphotropic phase boundary (MPB) composition looses piezoelectricity above its Curie temperature (TC) of 350°C. The maximum operating temperature is, however, limited to about 100°C below TC as operating at temperatures close to TC can result in gradual reduction in performance with time. In chemically modified PZT, known as “soft PZT”, TC can be as low as 190°C, which seriously limits its applicability at high temperatures.
Great efforts have been recently spent to replace PZT [1,2]. Improvements have been achieved by finding some alternative lead-free materials; however, they are suitable only for narrow application range [1]. The replacement of PZT on a broader basis is still acting as the major driving force for the research and development in the field of piezoelectric materials.
Environmental concerns and the need for better piezoelectric materials, capable to operate at elevated temperatures ()200°C), are presently leading to severe conditions for future development of piezoelectric ceramics and components. The solution is to create a platform of research and development activities, which would focus on basic studies of potential PZT-alternative candidates with high TC. This is the aim of the proposed project. The project, therefore, aims at creating a new step in the development of lead-free piezoelectric materials with high response and high operating temperature ()200°C). The strategy is two-fold: i) to explore ceramic materials of novel compositions based on BiFeO3 with high operating temperature and high response and ii) to integrate these new piezoelectric elements in thick-film structures and examine their operability at high temperatures, both pointing toward applications.
In the second part of the project (integration) we will collaborate with the research group HIPOT-RR, which is experienced in research, development and technology transfer of hybrid electronic thick-film microcircuits, sensors and other electro-mechanical systems. This will enable future transfer of knowledge into practice. Working simultaneously on materials development and their integration into sensor/actuator structures will create a basis for improved and new high-added-value products, which will preserve the competitiveness of Europe and Slovenia in the field.
References:
[1] Roedel et al., J. Am. Ceram. Soc. 92, 1153 (2009).
[2] Shrout and Zhang, J. Electroceram. 19, 111 (2007).
Significance for science
The achievement of the research project which represents an important contribution to science of ferroelectrics is the discovery of the mechanism of electrical conduction at domain walls in BiFeO3 (published in Nature Materials; Rojac et al., Nat. Mater. 16, 322–327, 2017). This fundamental study created the basis for future development of new materials based on BiFeO3 with improved properties associated with the dynamic behavior of domain walls under external fields. We also expect an impact of our work on studies devoted to the design of local properties in materials for nanoelectronics. To elucidate the conduction mechanism we developed two analytical microscopy techniques, thus creating tools for structural and chemical characterization of oxide materials on atomic scale. The studies published in Advanced Functional Materials (Rojac et al., Adv. Funct. Mater. 25, 2099–2108, 2015) revealed the missing bridge linking the local properties (measured on nano- and micrometer scale) with macroscopic properties of piezoelectrics (measured on millimeter scale). Considering that this relationship is responsible for the complex field, frequency and temperature dependency of the piezoelectric response it opens up new research horizons on polycrystalline ferroelectrics where the key role will be played by local conductive paths along domain walls and grain boundaries. The feature paper published in the Journal of the American Ceramic Society (Rojac et al., J. Am. Ceram. Soc. 97, 1933–2011, 2014) acts as a guideline in the search of highly performant and high-temperature piezoceramics based on BiFeO3 (55 citations, source: WoS). By presenting and explaining the key thermodynamics and kinetic aspects of the BiFeO3 processing we succeeded to establish a strong basis for processing of BiFeO3-based materials, thus stimulating further research in this area.
Significance for the country
The research project allowed us to acquire the critical knowledge, equipment and experiences in the field of piezoelectrics for high-temperature applications. On this basis we established the collaboration with the Slovenian company HIDRIA AET with which we are now developing high-temperature piezoelectric pressure sensors used in cold-start plugs for automotive engines of next generations. HIDRIA AET is one of the global leaders in the field of cold-start plugs. The project also made it possible to develop and construct complex measurement systems for high-temperature piezoelectric and dielectric characterization of piezoceramics. This is the first such system in Slovenia and will be fruitfully exploited to raise the level of Slovenian research and as a support for the HIDRIA AET company. Research studies published in most prestigious scientific journals have a considerable value. As they are top-rated, such studies have an enormous scientific influence, contributing to the world-wide recognition of their authors. This is particularly important in terms of invitations in research projects and international conferences. The paper published in Nature Materials, which is an exclusive result of Slovenian research work, thus opens wide opportunities for future collaborative work with most important institutions and universities world-wide. Only such publications provide to Slovenia the recognition of scientific excellence. Young researches were extensive involved in the research project. This resulted in 2 diploma theses, 2 master theses and 1 doctoral thesis. Education, training and active involvement of students in fundamental and applicative research studies raises the level of staff qualification in specialized areas, which is the key for intensifying the economic growth in small countries such as Slovenia. Some of the project results will have an impact in longer terms and are potentially important for Slovenia. Based on the achieved level of technological advances and depending on the decision of potential industrial partners it is possible that applicative or even industrial projects on high-temperature piezoelectric sensors and actuators will be soon launched. This is based on market and technology forecasts, which predict increasing demands (doubled each two years in the period between 2020 and 2024) for sensors and actuators or sensing systems in the fourth industrial revolution and the internet of things. Since demands for sensors and actuators for elevated temperatures (above 200°C) will also increase, we consider that some of the project results could be useful for the research-and-innovation projects with industry. Furthermore, the topic is compatible with the “Strategy for smart specialization” of Republic of Slovenia (S4), in particular with domains “Future factories” and “Mobility” in the priority field “Industry 4.0”. The topic is also relevant for EU projects within Horizon 2020 (program “Space”) and within European Space Agency (ESA) programs.
Most important scientific results
Annual report
2014,
2015,
final report
Most important socioeconomically and culturally relevant results
Annual report
2013,
2014,
2015,
final report
