Partner 1 (Project Coordinator) - Josef Stefan Institute (JSI), Slovenia

Project Manager: Dr. Marjeta Macek Krzmanc

Partner 2: Institute of Solid State Physics, University of Latvia (ISSP UL), Latvia

Head of the ISSP team: Prof. Eugene Kotomin

Partner 3: National Institute of Materials Physics (NIMP), Romania

Head of the NIMP team: Dr. Ioana Dorina Vlaicu

Members of the NIMP team: Dr. Ioana Dorina Vlaicu; Dr. Mariana Stefan; Dr. Daniela Ghica; Dr. Mihai Vlaicu; Dr. Adrian Valentin Maraloiu; Dr. Raluca Florentina Negrea; Dr. Ionel Florinel Mercioniu; Drd. Fiz. Andrei Cristian Kuncser; Ing. Stefan Bulat; Tehn. I. Ion Anton

Partner 4: Faculty of Electrical Engineering, Power Engineering and Information Technology, Technical University Iasi (TU Iasi), Romania

Head of the TU Iasi: Prof. Romeo Ciobanu

Partner 5: Intelectro Iasi SRL (ITL), Romania

Head of the ITL: Dr. Olga Plopa

Project Results

Stage 1 - 2016 of the HarvEnPiez project -

- Research concerning the piezoelectric and electromechanical properties of the particles and thin films.

   - Summary of the main project results for Stage 1 - 2016:

- Synthesis by coprecipitation of tetragonal BaTiO₃, even at a low temperature of 100^oC.

- Morpho-structural characterization of the perovskite nanoparticles by powder XRD, TEM, and EDS experimental techniques.

- TEM analysis showed that the BaTiO₃ sample calcined at 700^oC presents a general morphology of spheres/ plates with a narrow size distribution of 25-50 nm.

- Comsol MultiPhysics simulations related to the electromechanical response of BaTiO₃ films with different geometries.

- The topochemical conversion method from molten salt was used to obtain perovskite-type particles (BaTiO₃) with defined shapes and sizes starting from template-precursors with defined plate-like shape.

The objectives of the first stage - 2016 - were fulfilled and the expected results for this stage were accomplished.

- SYNTHETICAL SCIENTIFIC REPORT NR. 1 for 2016 in .pdf format available at UEFISCDI.

Stage 2 - 2017 of the HarvEnPiez project – Synthesis and morpho-structural characterization of the perovskite-type particles with defined shape (cubes, plates and/or wires)

Results:

-          An experimental model of two compositions for obtaining perovskite type particles with a defined shape.

-          Report concerning the morpho-structural characterization of the perovskite-type particles with a defined shape.

-          Dissemination of the results by attending a national conference with one poster and one international conference with one poster.

Activity 1. Synthesis of the perovskite-type particles with defined shape (cubes, plates and/or wires).

- Following two steps solid-state synthesis method there were obtained perovskite type particles with defined shape: plates and cubes, by varying x and y content of Ca and Zr, respectively, within the compositions: Ba_1-xCa_xTiO₃ and BaZr_yTi_1-yO₃.

Activity 2. Morpho-structural characterization of the perovskite-type particles with defined shape (cubes, plates and/or wires).

The particles obtained in Activity 1 were characterized by both structural and morphological point of view by powder XRD, TEM, EDX, SEM experimental techniques.

Morpho-structural characterization of the perovskite-type particles obtained from the Ba_1-xCa_xTiO₃ (x=0-1) composition

XRD results

TEM results

SEM results

Morpho-structural characterization of the perovskite-type particles obtained from the BaZr_yTi_1-yO₃ (y=0-1) composition

XRD results

TEM results

SEM results

Activity 3. Attending conferences and/or publications in ISI journals. Updating the project website.

The results of the first and second stage of the HarvEnPiez project were presented this year in the frame of two conference attendings with two posters:

- CREMS 2017 "CONFERENCE OF THE ROMANIAN ELECTRON MICROSCOPY SOCIETY", SINAIA, ROMANIA, 16-18.05.2017 -

POSTER TYPE PRESENTATION:

TITLE: “Microstructural characterization of BaTiO₃ nanoparticles using TEM techniques: the effects of post-synthesis treatments”

AUTHORS: Ioana-Dorina Vlaicu, Raluca Florentina Negrea, Valentin-Adrian Maraloiu, Ionel Florinel Mercioniu

- NANOCON 2017 "9^TH INTERNATIONAL CONFERENCE ON NANOMATERIALS - RESEARCH & APPLICATION", BRNO, CZECH REPUBLIC, 18.10.-20.10.2017

POSTER TYPE PRESENTATION:

TITLE: „Influence of Calcium Content on Morpho-structural Properties of the Perovskite-type Structure Ba_1-xCa_xTiO₃”

AUTHORS: Ioana D. Vlaicu^*, Marjeta Maček Kržmanc, Danilo Suvorov, Adrian V. Maraloiu, Ionel F. Mercioniu, Raluca F. Negrea, Andrei C. Kuncser, Daniela Ghica, Mariana Stefan, Mihai A. Vlaicu

The objectives of the second stage - 2017 - were fulfilled and the expected results for this stage were accomplished.

- SYNTHETICAL SCIENTIFIC REPORT NR. 2 for 2017 in .pdf format available at UEFISCDI.

Stage 3 - 2018 of the HarvEnPiez project – Integration of ferroelectric particles in thin films and their characterization.

This stage's objectives:

1. Selecting and design of the self-assembling/ integration of the particles in thin films.
2. Study of the structural and microstructural characteristics of the thin films and ceramics.
3. Optimization of the production technology of the nano-piezoelectric devices. Modeling nano-piezoelectric devices.
4. Results dissemination through participation to national/ international conferences. Project webpage updating.

Results:

• Report concerning technical recommendations for choosing the self-assembling/ integration of the ferroelectric particles and the substrate for the thin films;
• Report concerning the microstructural characterization of the thin films and ceramics;
  • - Report concerning the electrical properties of the thin films;

• Recommendation for modeling and optimization of the production technology for nano-piezoelectric devices;

• Report concerning the dissemination activities.

Activity 3.1. Selecting and design for the self-assembling method of the particles.

For the integration of the ferroelectric particles in thin films two methods were chosen: self-assembling from the water-oil interface and spin-coating of the composites (ferroelectric particles dispersed into a polymeric matrix). For these two methods, different substrates were considered, e.g. ITO/glass, ITO/PET, Si/Pt, glass.

Accordingly, thin films with different thicknesses and compositions were obtained, both as rigid and flexible films.

Activity 3.2. Studies concerning the structural and microstructural characteristics of thin films and ceramics.

The thin films obtained by the two selected methods in Activity 3.1 where characterized by optical microscopy, XRD, SEM and also their electrical properties were evaluated.

The optical microscopy provided first global information about the degree of coverage of the substrates used for self-assembling or for spin-coating. Examples of images taken with the optical microscope are given in figure 1.

 A)           B)

Figure 1. Self-assembled particles on Pt/Si substrate from the interface: A) isopropanol-toluene, functionalized particles with oleic acid; B) isopropanol-octadecane, unfunctionalized particles

XRD results indicated the preferential orientation of the BaTiO3 plate-like ferroelectric particles on the substrate when self-assembled at the water-oil interface, as it can be observed in Figure 2 A. The thin films obtained by spin-coating of BaTiO3 particles dispersed in PDMS present an XRD diffractogram in which all crystalline directions are visible (Figure 2B).

A)

Figure 2. XRD diffractograms for A) thin film of self-assembled BaTiO3 plate-like particles functionalized with SILAN, on a glass substrate; B) thin film deposited by spin-coating on ITO/PET substrate of a composite with the composition 70% BaTiO3 - 30% PDMS.

SEM images revealed a better self-assembling with a preferential orientation of the plate-like particles on the substrate when particles are functionalized with SILAN rather than when they are unfunctionalized (figure 3), and also the particles are less agglomerated when functionalized.

  A)     B)

Figure 3. SEM micrographs of thin films obtained by self-assembling on a glass substrate of A) unfunctionalized BaTiO3 particles; B) SILAN functionalized BaTiO3 particles.

Dielectric constant measurements evidenced a direct dependency of the dielectric constant upon the film thickness and the amount of BaTiO3 particles in the composite spin-coated on the substrate.

Activity 3.3. Optimization of the production technology for nano-piezoelectric devices. Modeling nano-piezoelectric devices.

In collaboration with our partners Technical University "Gheorghe Asachi" from Iasi the modeling of the nano-piezoelectric devices was made using the finite element model which is based on a dedicated software, for example with COMSOL Multiphysics, on the ground of "structural mechanics" with 'piezoelectric' routine in the ADD PHYSICS group and by selecting Eigen frequency in STUDIES.

Production technology consisted of three stages:

1. Powder elaboration for ink production - activity performed by NIMP team

2. Ink production - activity performed by NIMP team

3. Ink-jet printing - activity performed by partners from SC Intelectro SRL.

Activity 3.4. Participation at national/ international conferences and submitted/ published papers. Updating the project web page. 

• 3 attendances to 2 international conferences:

- 2 posters presented at the International Conference “Electron Microscopy of Nanostructures ELMINA2018 Conference” held in Belgrade, Serbia, between 27.08-29.08.2018:

"Solubility limits and microstructural changes induced by Ca content in the Ba_1-xCa_xTiaO₃ perovskite-type particles",

authors: Ionel F. Mercioniu, Marjeta Macek Krzmanc, Daniela Ghica, Adrian V. Maraloiu, Ioana D. Vlaicu – poster PO 1.7 in Elmina 2018 Book of Abstracts.

"Influence of Zr concentration on the morphology and structure of BaTi_1-yZr_yO₃",

authors: Valentin A. Maraloiu, Ioana D. Vlaicu, Marjeta Macek Krzmanc, Ionel F. Mercioniu, Daniela Ghica – poster PO 1.25 în Elmina 2018 Book of Abstracts.

- 1 oral presentation at the International Conference “2018 International Conference and Exposition on Electrical and Power Engineering (EPE)” held in Iași, Romania, between 18.10-19.10.2018:

"Limits and Particularities of the Synthesis of Ba_1-xCa_xTiO₃ for Piezoelectric Applications, by Topochemical Conversion from Molten Salt Solutions",

authors: Ioana D.Vlaicu, Marjeta Maček Kržmanc, Adrian V. Maraloiu, Daniela Ghica, Ionel F. Mercioniu, Mariana Ștefan, Mihai A. Vlaicu, Raluca F. Negrea, Andrei C. Kuncser, S. Bulat, Romeo C. Ciobanu, Olga Plopa – paper 3657 in EPE 2018 Book of Abstracts.

- 1 paper submitted for publication in Journal of Physical Chemistry C (F.I.= 4,484) together with the partners from Slovenia (IJS) and Latvia (UL ISSP), with the title:

"Theoretical and Experimental Study of Structural and Piezoelectric Properties of (Ba, Sr)TiO₃ Perovskite Solid Solutions and BaTiO₃/SrTiO₃ heterostructures",

and authors: Leonid L. Rusevich, Guntars Zvejnieks, Eugene A. Kotomin, Marjeta Maček Kržmanc, Anton Meden, Špela Kunej, Ioana D. Vlaicu –

paper status: submitted + first revision (Manuscript ID: jp-2018-09750v.R1).

The objectives of the third stage - 2018 - were fulfilled and the expected results for this stage were accomplished.

- SYNTHETICAL SCIENTIFIC REPORT NR. 3 for 2018 in .pdf format available at UEFISCDI.

Stage 4 - 2019 of the HarvEnPiez project – Development of energy management concept with a demonstration of use, prototyping and related feasibility studies. This project stage carries in collaboration with partners TU Iași and Intelectro Iași SRL. 

This stage's objectives:

1. Risk assessment regarding the concept of energy harvesting.
2. Costs vs. benefits analysis on adopting the concept for energy applications.
3. Dissemination and implementation of the results. Project webpage updating.

Results:

• Report on the feasibility study.
• Dissemination of the final results at the last meeting with the HarvEnPiez partners and by updating the project webpage.
• Publication of 1 scientific paper in Journal of Physical Chemistry C (F.I.= 4,484) together with the partners from Slovenia (IJS) and Latvia (UL ISSP), with the title:"Theoretical and Experimental Study of Structural and Piezoelectric Properties of (Ba, Sr)TiO₃ Perovskite Solid Solutions and BaTiO₃/SrTiO₃ heterostructures",and authors: Leonid L. Rusevich, Guntars Zvejnieks, Eugene A. Kotomin, Marjeta Maček Kržmanc, Anton Meden, Špela Kunej, Ioana D. Vlaicu –

  paper status: published

The objectives of the fourth stage - 2019 - were fulfilled and the expected results for this stage were accomplished.

- SYNTHETICAL SCIENTIFIC REPORT NR. 4 for 2019 in .pdf format available at UEFISCDI.

Theoretical and Experimental Study of (Ba, Sr)TiO₃ Perovskite Solid Solutions and BaTiO₃/SrTiO₃Heterostructures

• Leonid L. Rusevich*
• Guntars Zvejnieks
• Eugene A. Kotomin
• Marjeta Maček Kržmanc
• Anton Meden
• Špela Kunej
• Ioana D. Vlaicu