Journal of Advanced Dielectrics
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2023
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IF 3.1
Xinyu Bu,Changhong Yang,Mengjia Fan,Wenxuan Wang,Xiujuan Lin,Shifeng Huang
Lead-free ( K 0 . 5 Na 0 . 5 )NbO 3 (KNN) and Li 0 . 0 6 ( K 0 . 5 Na 0 . 5 ) 0 . 9 4 NbO 3 (LKNN) thin films were fabricated by a sol-gel method. The effects of Li substitution on crystal structure, microstructure and electrical properties of KNN film were systematically studied. Li doping can enhance the ferroelectric and piezoelectric properties of KNN film. Compared with pure KNN film, the LKNN film possesses larger remanent polarization ( P r ∼ 9.3 μ C/ cm 2 ) and saturated polarization ( P s ∼ 41.2 μ C/ cm 2 ) and lower leakage current density ( ∼ 1 0 − 5 A/ cm 2 at 200 kV/cm). Meanwhile, a typical butterfly shaped piezoelectric response curve is obtained in the LKNN film with a high piezoelectric coefficient ( d 3 3 ∼ 105 pm/V). Excellent fatigue resistance ( ∼ 1 0 9 switching cycles) and aging resistance ( ∼ 180 days) demonstrate the long-term working stability of LKNN film. These findings indicate that KNN-based lead-free piezoelectric films have a broad application prospect in microelectromechanical systems (MEMS).
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Hsin Wang,Hua Hao,Dongxu Li,Huihuang Xu,Qinghu Guo,Minghe Cao,Zhonghua Yao,Hanxing Liu
Lead-free thin film capacitors with high energy density and efficiency are promising candidates for pulse power systems in advanced electronic industries due to their low cost, lightweight, and integration development. In this study, 0.6Bi 0.5 Na 0.5 TiO 3 -0.4Sr 0.7 Bi 0.2 TiO 3 + x mol Mn (BNT-SBT- x Mn) thin films are fabricated on Pt/Ti/SiO 2 /Si substrates via sol-gel method. The BNT-SBT- x Mn films with perovskite phase possess uniform grain size, well density, and low roughness. The introduction of Mn ions compensates for valence unbalances of A-site vacancy of BNT-based films and forms defective dipoles. Their synergism hinders the transmission of carriers, reduces the leakage current density, and improves polarization and breakdown behavior. Therefore, the BNT-SBT-2% Mn film achieves a high recoverable energy density of 85.35 J/cm 3 together with an enhanced energy efficiency of 73.17% under an electric field of 3114 kV/cm. Meanwhile, the BNT-SBT-2% Mn film displays a good frequency (10 Hz-2k Hz), temperature (20–200 °C), and fatigue (1-10 5 cycles) stability in electrical energy storage properties, suggesting that it would be a promising candidate for the advanced power systems.
研究领域:
材料科学
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电子工程
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Chengwen Bin,Xu Hou,Zeqing Yu,Luocheng Liao,Han Yang,Yunya Liu,Jie Wang
Flexible ferroelectric films with high polarization hold great promise for energy storage and electrocaloric (EC) refrigeration. Herein, we fabricate a lead-free Mn-modified 0.75 Bi(Mg0.5Ti0.5)O3–0.25 BaTiO3 (BMT–BTO) thin film based on a flexible mica substrate. Excellent EC performance with maximum adiabatic temperature change (ΔT ∼23.5 K) and isothermal entropy change (ΔS ∼33.1 J K–1 kg–1) is achieved in the flexible BMT–BTO film, which is attributed to the local structural transition and lattice disorder near 90 °C. Meanwhile, a good energy storage density of ∼70.6 J cm–3 and a quite high efficiency of ∼82% are realized in the same ferroelectric film, accompanied by excellent stability of frequency and electric fatigue (500–10 kHz and 108 cycles). Furthermore, there is no apparent variation in performance under different bending strains. These prominent properties indicate that the multifunctional BMT–BTO ferroelectric film is a promising candidate for applications of flexible energy storage and EC refrigeration.
研究领域:
材料科学
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能源技术
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Chengwen Bin,Xu Hou,Han Yang,Luocheng Liao,Yadan Xie,Hua Wei,Yunya Liu,Xumin Chen,Jie Wang
Flexible dielectric film capacitors with high performance of energy storage has shown great promise as a solution to the flexibility and stability of modern electronics and electric power systems. Herein, a novel relaxor-ferroelectric BiMg 0.5 Ti 0.5 O 3 - x SrTiO 3 (BMT- x STO, x = 0.1, 0.2, 0.3 and 0.4) thin film capacitors are obtained via one-step fabrication on flexible mica substrates. A superior energy storage density of 109.7 J cm −3 and a pretty high efficiency of 80.6% are simultaneously achieved in the BMT-0.3STO film capacitor. At the same time, the energy storage performance can be stable in the temperature range of 25 to 200° C, the wide frequency range of 500 Hz to 10 kHz, and even after 10 8 electrical cycles. In addition, under the bending radii from 16 mm to 4 mm, there is no obvious variation in performance even after 10 4 mechanical fatigue cycles, indicating the super flexibility and stability of the film capacitors. The prominent properties of the BMT-based film capacitor are mainly attributed to the improvement of relaxation behavior by introducing appropriate STO, which are explained by the domain evolution via piezo-response force microscopy and phase field simulation. The present work suggests a new way to obtain lead-free and flexible dielectric film capacitors for flexible energy storage technology.
研究领域:
材料科学
·
能源技术
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·Vol. 49
·期 23
·39700-39706
·
IF 5.2
Xinkun Liu,Ying Dai,Xinmei Pei,Wen Chen
Ferroelectric thin films with giant room-temperature electrocaloric effect (ECE) could be very useful in design of solid-state refrigeration devices. Here, lead-free Ba 0.85 Ca 0.15-x Sr x Zr 0.1 Ti 0.9 O 3 (BCZT-xSr, 0.01 ≤ x ≤ 0.10) thin films are successfully prepared on the substrates (Pt/Ti/SiO 2 /Si) via sol-gel route, and the effect of the Sr substitution on the structure, electric properties and ECE of the films were investigated. The dielectric analyses show that the rhombohedral-tetragonal phase transition temperature (T R-T ) move to a higher temperature and the tetragonal-cubic phase transition temperature (T m ) shift to a lower temperature with increasing Sr content, and finally the T R-T peaks merge into the T m peaks at room temperature. The BCZT-0.05Sr film presents a giant ECE with ΔT = 27.1 K and ΔS = 30.6 J K −1 kg −1 at 800 kV cm -1 near room temperature (301 K). The giant ΔT benefits from a multiphase coexisting region with successive R-T and T-C phase transition character near room temperature. These results indicate that the lead-free Sr-doped BCZT thin film is an attractive material for application in ECE refrigeration devices.
研究领域:
材料科学
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凝聚态物理
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功能材料
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热电转换
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固态制冷
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·Vol. 49
·期 2
·1846-1854
·
IF 5.532
Xinkun Liu,Ying Dai,Xinmei Pei,Wen Chen
The electrocaloric (EC) effect cooling technique of environmentally friendly lead-free thin film materials driven by electric fields has recently gained tremendous attention due to the urgent demand for microelectronic and integrated circuit refrigeration devices. However, the widespread use of lead-free materials in EC devices is seriously hindered due to the small electrocaloric temperature change (ΔT) within a narrow operation temperature span (T span ) near room temperature. Here, lead-free Ba 0.85 Ca 0.15 Zr 0.1 Ti 0.9-x Sn x O 3 (BCZT-xSn, 0 ≤ x ≤ 0.03) thin films were prepared on substrates (Pt/Ti/SiO 2 /Si) via a sol-gel route. The BCZT-0.02Sn thin film presents an excellent EC effect (ΔT = 32.74 K, ΔS = 37.18 J kg −1 K −1 ) and large EC strength (ΔT/ΔE = 0.033 K cm kV −1 , ΔS/ΔE = 0.037 J cm K −1 kg −1 kV −1 ) over a wide T span (∼26 K) under 1000 kV cm −1 near room temperature. The giant ΔT is mainly attributed to the emergence of an intermediate O phase and the formation of a multiphase (R, O and T phases) coexistence structure at room temperature, while the diffuse phase transition behavior is responsible for the wide T span . Our study provides a new idea for developing environment-friendly EC materials with an excellent room-temperature ΔT over a broad operational temperature region.
研究领域:
材料科学
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功能材料
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固态物理
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环境友好材料
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制冷技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）