Abstract

Aurivillius ferroelectrics K(0.25)Na(0.25)La(0.5)Bi(2)Nb(2)O(9) (KNBN-La) and K(0.25)Na(0.25)Bi(2.5)Nb(2)O(9) (KNBN-Bi) were prepared by using solid-state reaction process. Rietveld refinements for the KNBN-La and KNBN-Bi were carried out by using powder X-ray diffraction at room temperature and they were confirmed to be two-layer Aurivillius oxides with orthorhombic space group A2(1)am. The lattice parameters are a = 5.50468(10) Å, b = 5.49217(10) Å, and c = 25.05108(35) Å for KNBN-La and a = 5.48867(6) Å, b = 5.47895(6) Å, and c = 25.10591(25) Å for KNBN-Bi. Lanthanum (La(3+)) substitution for bismuth (Bi(3+)) led to an enhancement in relaxation behavior for the KNBN-La ceramics, with a ferroelectric to paraelectric phase transition temperature (T(c)) of about 360 °C. The KNBN-La ceramics had a high remnant polarization (P(r)) of 13.6 μC cm(-2) and a field-induced strain of up to 0.031%. Particularly, the decrease in P(r) for the KNBN-La ceramics after 10(8) cumulative switching cycles was only 6%.

Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call