Study of structure and dielectric response of the ferroelectric composites (1 − x)NaNO₂ + (x)KNO₂ at x = 0.05, 0.1 and 0.2

Abstract

The study of crystal structure temperature evolution of the ferroelectric composites (1 − х)NaNO₂ + (x)KNO₂ at х = 5, 10 и 20 vol. % has been performed by neutron diffraction. The temperature dependencies of the ferroelectric order parameter η(т) for sodium nitrite have been determined in the composites and pure NaNO₂. They coincide on heating and cooling and do not depend on KNO₂ concentration. The increasing of KNO₂ structural phase transition temperature (∼10–15 K) has been revealed in the composites in comparison with pure KNO₂.

Keywords:

• Ferroelectrics
• composites
• phase transitions
• neutron diffraction

Acknowledgments

The authors are grateful Helmholz Zentrum Berlin (Berlin, Germany) for the provision the experimental time on the neutron diffractometer E2.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by Ministry of Science and Education of the Russian Federation under Grant number 3.1150.2017/4.6.