(Na0.8-xK0.2Lix)0.5Bi0.5Ti0.985Ta0.015O3 lead-free ceramics with large strain and high recoverable energy density

The conventional solid reaction was used to synthesize (Na0.8-xK0.2Lix)(0.5)Bi0.5Ti0.985Ta0.015O3 (abbreviated as BNKTT-100xLi) lead-free perovskite ceramics. The influences of Li+ ion doping for the relaxation mechanism and piezoelectric performances of all ceramics were systematically investigated. All ceramics exhibited a single perovskite structure, accompanied with a dense surface morphology and uniform element distribu-tions. AC impedance spectroscopy showed the single grain conduction mechanism for all samples. The maximum bipolar strain (S = 0.462%) and unipolar strain (S-u = 0.443%) for x = 0.025 sample were obtained under 80 kV/cm, and its unipolar strain achieved 0.573% at 100 degrees C. BNKTT-15Li ceramic exhibited outstanding energy storage performance with a recoverable energy density of 1.29 J/cm(3) under applied 130 kV/cm field. It suggested that the excellent electro-strain and energy-storage properties for BNKTT-100xLi ceramics could be widely applicable to electronic equipment. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

This study synthesized lead-free perovskite ceramics using a traditional solid reaction and investigated the effects of Li+ ion doping on the relaxation mechanism and piezoelectric performance. The ceramics showed excellent electro-strain and energy storage properties, making them suitable for electronic equipment applications.