AUTHOR=Huo Ziwei , Xie Hang , Xu Jiwen , Yang Ling , Qiu Wei , Zhang Xiaowen , Zhou Changrong , Wang Hua 

TITLE=Tailoring the Structure, Energy Storage, Strain, and Dielectric Properties of Bi0.5(Na0.82K0.18)0.5TiO3 Ceramics by (Fe1/4Sc1/4Nb1/2)4+ Multiple Complex Ions

JOURNAL=Frontiers in Materials

VOLUME=7

YEAR=2020

URL=https://www.frontiersin.org/journals/materials/articles/10.3389/fmats.2020.00008

DOI=10.3389/fmats.2020.00008

ISSN=2296-8016

ABSTRACT=<p>The effects of (Fe<sub>1/4</sub>Sc<sub>1/4</sub>Nb<sub>1/2</sub>)<sup>4+</sup> (FSN) multiple complex ions on the structure and electrical properties of Bi<sub>0.5</sub>(Na<sub>0.82</sub>K<sub>0.18</sub>)<sub>0.5</sub>Ti<sub>(1−x)</sub>(Fe<sub>1/4</sub>Sc<sub>1/4</sub>Nb<sub>1/2</sub>)<sub><italic>x</italic></sub>O<sub>3</sub> (BNKT-<italic>x</italic>FSN) ceramics were studied. The FSN complex ions induce the phase transition from ferroelectric state to relaxor state. The coercive field and remanent polarization decrease rapidly with the increase of FSN content. With the increase of the external electric field, the energy storage density of BNKT-<italic>x</italic>FSN ceramics gradually increases and reaches the maximum value of 0.96 J/cm<sup>3</sup> (90 kV/cm) at <italic>x</italic> = 0.09, and the corresponding efficiency is 62%. Meanwhile, the field-induced strain of BNKT-0.07FSN ceramic increases from 0.13% at 50 kV/cm to 0.43% at 80 kV/cm, and the corresponding electrostrictive coefficient <italic>Q</italic><sub>33</sub> reaches the maximum value of 0.0213 m<sup>4</sup>/C<sup>2</sup>. BNKT-<italic>x</italic>FSN relaxed ceramics with pseudo-cubic structure have large electrostrictive coefficients when <italic>T</italic><sub>d</sub> is near room temperature. The local composition inhomogeneity by FSN complex ions at B-sites induces the relaxor characteristics of BNKT-<italic>x</italic>FSN ceramics.</p>