Effect of Zr Doping on Structural and Ferroelectric Properties of Lead-Free Bi0.5(Na0.80K0.20)0.5TiO3 Films

Advances in Condensed Matter Physics

Toàn

Hùng

2019

Self Cite

Lead-free Bi0.5(Na0.80K0.20)0.5TiO3 (BNKT) ferroelectric films were synthesized on Pt/Ti/SiO2/Si substrates via chemical solution deposition. The influence of crystallization time on the microstructures and ferroelectric and energy-storage properties of the films was investigated in detail. The XRD analysis showed that the BNKT films have well crystallized corresponding to the single-phase perovskite structure at 700°C. Ferroelectric and energy-storage properties of the films were significantly enhanced by increasing crystallization time. With crystallization time of 60 min, the remnant polarization (Pr), maximum polarization (Pm), and Pm-Pr values reached the highest values of 7.9 µC/cm2, 28.9 µC/cm2, and 21.0 µC/cm2, respectively, under the electric field of 400 kV/cm. Thanks to the strong enhancement in Pm and the large Pma-Pr value, the highest recoverable energy-storage density (Jreco) gets the value of 2.9 J/cm3. The obtained results indicate that the BNKT films have application potentials in advanced capacitors.

Section: Resultssupporting

confidence: 93%

Influence of Crystallization Time on Energy-Storage Density and Efficiency of Lead-Free Bi_0.5(Na_0.8K_0.2)_0.5TiO₃ Thin Films

Advances in Condensed Matter Physics

Toàn

Hùng

2019

Self Cite

“…The phase structure of BNKT multilayer film is typified by the peaks (marked by a $ sign), as (110) at around 32°and (200) at around 47°. This observation matches with previous works, 13,22) which reported that BNKT films possess an MPB component with rhombohedral and tetragonal symmetries. The cubic structure of BZO film shows the characteristic peaks (marked by a @ sign) as (100) at 30°and (200) at 43°.…”

supporting

confidence: 93%

“…12) Among lead-free materials, the Bi(Na,Ka)TiO3 (BNKT) system is thought to be a potential candidate and likely replacement for PZT, because similar to Pb 2+ , Bi 3+ ions possess strong polarizability. 13) Earlier studies showed that BNKT compounds at the morphotropic phase boundary (MPB) reveal excellent electromechanical behaviors and coupling. 14) Their key properties such as remnant polarization (Pr ∼ 38 μC cm −2 ), piezoelectric coefficient (d 33 ∼ 167 pC N -1 ) or electromechanical coupling coefficient (k 33 ∼ 0.56) are able to compare with those of PZT.…”

mentioning

confidence: 99%

Influence of heterostructure on structure, electric and magnetic properties of Bi_0.5(Na_0.80,K_0.20)_0.5TiO₃/BaZrO₃ films prepared by the sol–gel method

Tuấn

Minh

et al. 2023

Jpn. J. Appl. Phys.

Self Cite

This study reports on structure, electric and magnetic properties of the BNKT/BZO heterolayered films synthesized via chemical solution deposition on Pt/Ti/SiO2/Si substrates. The inﬂuence of different heterolayered configurations on the microstructure, electric and magnetic properties of the ﬁlms was investigated thoroughly. Magnetic properties and leakage current density (J) of the ﬁlms were expressively improved thanks to the heterolayered structures. Heterolayered films M42 yield highest Ms and Mr values of 14.4 emu/cm3 and 1.7 emu/cm3, respectively about 3 times higher than multilayered BNKT. Thanks to heterolayered structures, J decreases strongly from 16.0x10-4 A/cm2 for BNKT films to 1.4x10-4 A/cm2 for heterolayered films M42. Obtained results show that the BNKT/BZO heterolayered films may become environmentally-friendly applicants for multifunction devices.

“…e crystalline structures of BNKT films are deduced from X-ray diffraction patterns in the 2θ ranges of 25°-75°s hown in Figure 2(a). All films are well crystallized corresponding to the single-phase perovskite structure, and no other impurity phases are detected [19,20]. BNKT films in this study possess the optimal composition near the MPB evidenced by the coexisting of rhombohedral and tetragonal phases [21].…”

Section: Resultsmentioning

confidence: 61%

Influence of Crystallization Temperature on Structural, Ferroelectric, and Ferromagnetic Properties of Lead-Free Bi_0.5(Na_0.8K_0.2)_0.5TiO₃ Multiferroic Films

Advances in Materials Science and Engineering

Toàn

Hùng

et al. 2019

Self Cite

Lead-free Bi0.5(Na0.8K0.2)0.5TiO3 (abbreviated as BNKT) films have been synthesized via a sol-gel technique on Pt/Ti/SiO2/Si substrates, and the dependence of the physical properties in BNKT films were investigated as a function of the crystallization temperature. The BNKT films were annealed at different temperatures (600, 650, 700, and 750°C) for 60 min in the air. The results of this study showed that the optimal crystallization temperature is 700°C. At this, the BNKT films exhibited a single perovskite phase structure and high-dense surface. Besides, the remanent (Pr) and maximum (Pm) polarization reached their highest values of 9.2 µC/cm2 and 30.6 µC/cm2, respectively. All the films showed a weak ferromagnetic behavior with the maximum saturated magnetization (Ms) of 2.1 emu/cm3. These values are equivalent to the highest Pr and Pm values in previous reports on lead-free films.