Microstructure and phase transition of lead‐free (Bi_1/2Na_1/2)TiO₃‐based ferroelectrics via different Li⁺ introduction sources

Abstract

Lead‐free 0.85(Bi1/2Na1/2)TiO3‐0.10(Bi1/2K1/2)TiO3‐0.05BaTiO3 (BNKBT) ceramics with Li2CO3 or (Bi1/2Li1/2)TiO3 (BLT) added were fabricated by conventional solid oxide route. The XRD analysis indicated that Li2CO3 introduction led to increasing fraction of tetragonal phase while BLT introduction gave a reverse tendency. Meanwhile, the depolarization temperature Td of Li2CO3‐added BNKBT ceramics was clearly enhanced, while that of BLT‐added BNKBT ceramics went down as the added amount increased. The similarity in variation of the phase structure and the Td of BNKBT ceramics revealed the nature of the Li+ introduction source on phase structure in BNKBT ceramics.

Influence of Al2O3nanoparticle doping on depolarization temperature, and electrical and energy harvesting properties of lead-free 0.94(Bi0.5Na0.5)TiO3–0.06BaTiO3ceramics

“…This conrms that the diffuse phase transition is stronger for the compositions with a higher Al 2 O 3 content. Several methods to determine the thermal depolarization temperature (T d ) can be found in the literatures 14,[41][42][43][44] including the thermally stimulated depolarization current (TSDC), temperature dependent in situ d 33 , dielectric permittivity and dielectric loss, piezoelectric resonance measurements, and high-temperature in situ XRD. 14 However, the TSDC method is one of the most popular techniques.…”

Complex Impedance Analyses of Ba_1-<i>_x</i>Li_0.5<i>_x</i>Bi_0.5<i>_x</i>TiO₃ Solid Solution PTCR Ceramics

“…It was found that increase in the bismuth lithium titanate content leads to a decrease in the Curie temperature in the system (Na 0.5 K 0.5 )NbO 3 . In contrast to these data, the authors of [7] showed that the introduction of lithium ions to the sodium-potassium sublattice leads to an increase in the Curie temperature in the system [Bi 0.5 (Na 1-x-y K x Li y ) 0.5 ]TiO 3 . It was shown that increasing lithium-bismuth titanate concentration leads to an increase in resistance and Curie temperature in Nb-doped PTCR solid solutions based on Ba 1−x Bi 0.5x Li 0.5x Ti 1-y Nb y O 3 from 120ºC to 150ºC in the range of 0≤x≤0.03 [8].…”