Antiferroelectrics exhibit a large potential for the use in various electronic devices due to their high energy-storage density (capacitors), field-dependent permittivity (tunable dielectrics), inverse electrocaloric effect (solid-state coolers), and multiple non-volatile states (neuromorphic computing). We are developing new lead-free antiferroelectric material compositions, explore their characteristics and limitations, and study the underlying physical mechanisms responsible for their unique behavior.
We developed a new lead-free antiferroelectric compositions based on the NaNbO3-SrSnO3 system, with a reversible room-temperature E-field-induced transition. Changing the composition enabled the transition between antiferroelectric states (with room-temperature double polarization loops) and relaxor states.
Studies of the field-induced transitions in pure NaNbO3 revealed irreversible phase transition behavior and gave further insights into the transition mechanism. We demonstrated the existence of a new phase transition between ferroelectric and antiferroelectric states, which can be induced by changing the grain size of polycrystalline samples.
ZHANG, Mao-Hua, FULANOVIĆ, Lovro, EGERT, Sonja, DING, Hui, GROSZEWICZ, Pedro B., KLEEBE, Hans-Joachim, MOLINA-LUNA, Leopoldo, KORUZA, Jurij. Electric-field-induced antiferroelectric to ferroelectric phase transition in polycrystalline NaNbO3. Acta Materialia, 2020, vol. 200, 127-135.
ZHANG, Mao-Hua, FULANOVIĆ, Lovro, ZHAO, Changhao, KORUZA, Jurij. Review on field-induced phase transitions in lead-free NaNbO3-based antiferroelectric perovskite oxides for energy storage. Journal of Materiomics, 2022, vol. 9, 1-18.
KORUZA, Jurij*, GROSZEWICZ, Pedro*, BREITZKE, Hergen, BUNTKOWSKY, Gerd, ROJAC, Tadej, MALIČ, Barbara. Grain-size-induced ferroelectricity in NaNbO3. Acta Materialia, 2017, vol. 126, 77-85. (* co-first authors)
Assoc. Prof. Dr. Jurij Koruza
Institute for Chemistry and Technology of Materials
Stremayrgasse 9
A-8010 Graz
Phone: +43 (0)316 873-32305
jurij.koruza @tugraz.at
FLAME project
Hessian Ministry of Science and Art
LOEWE funding programme