Abstract
In recent years, there is a growing interest for new lead-free oxides with reversible antiferroelectric (AFE)-ferroelectric (FE) phase transition for high-power energy-storage applications. NaNbO3-based ceramics are particularly attractive due to their easy synthesis and cost-effectiveness. In order to stabilize reversible AFE-FE phase transition, NaNbO3 is doped with a combination of heterovalent substitutions, although the underlying structural mechanism for the same is poorly understood. Here, we investigated local and average structures of Ca/Zr doped NaNbO3 using neutron total scattering. We show that Ca/Zr doping increases the average AFE phase (Pbma) fraction, however, the material remains as a composite of both FE (P21ma) and AFE regions. Analysis of local structure suggests that increase in the long-range AFE phase results from more extensive twinning of local FE regions, due to introduced charge disorder. We propose that enhanced energy-storage properties of Ca/Zr-doped NaNbO3 arises from localized twin boundary motion between the defect-induced pinning centers.
| Original language | English |
|---|---|
| Pages (from-to) | 1597-1609 |
| Number of pages | 13 |
| Journal | Journal of the European Ceramic Society |
| Volume | 44 |
| Issue number | 3 |
| DOIs | |
| State | Published - Mar 2024 |
Funding
The work described in this paper was partially supported by a grant from the Research Grants Council of the Hong Kong Special Administrative Region, China (Project No. CityU 11306720). F.P.M. and M.R.V.J. thank the Danish Agency for Science, Technology, and Innovation for funding the instrument center DanScatt. Affiliation with the Center for Integrated Materials Research (iMAT) at Aarhus University is gratefully acknowledged. A portion of this research used resources at the Spallation Neutron Source, a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory (IPTS-27376 for POWGEN experiments). L.D. and A.P. would like to acknowledge the support from University Paris-Saclay in the framework of the d′Alembert fellowship program. AP gratefully acknowledges Aurore Brezart-Oudot for assistance with SEM. The work described in this paper was partially supported by a grant from the Research Grants Council of the Hong Kong Special Administrative Region , China (Project No. CityU 11306720 ). F.P.M. and M.R.V.J. thank the Danish Agency for Science, Technology, and Innovation for funding the instrument center DanScatt. Affiliation with the Center for Integrated Materials Research (iMAT) at Aarhus University is gratefully acknowledged. A portion of this research used resources at the Spallation Neutron Source, a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory (IPTS-27376 for POWGEN experiments). L.D. and A.P. would like to acknowledge the support from University Paris-Saclay in the framework of the d′Alembert fellowship program . AP gratefully acknowledges Aurore Brezart-Oudot for assistance with SEM.
| Funders | Funder number |
|---|---|
| Center for Integrated Materials Research | |
| Research Grants Council of the Hong Kong Special Administrative Region , China | CityU 11306720 |
| Office of Science | |
| Oak Ridge National Laboratory | IPTS-27376 |
| Aarhus Universitet | |
| Danish Agency for Science and Higher Education | |
| Research Grants Council, University Grants Committee | |
| Université Paris-Saclay |
Keywords
- Antiferroelectric/ferroelectric
- Neutron scattering
- Pair distribution function
- Phase transition