CERAMICS INTERNATIONAL
·
2016
·Vol. 43
·期 3
·2969-2973
·
IF 2.758
Bing Xie,Haibo Zhang,Hao Kan,Sisi Liu,Ming-Yu Li,Zeyu Li,Shuai Zhu,Shiyong Qiu,Shenglin Jiang
This work demonstrates a highly efficient method for large-scale synthesis of elongated BaTiO 3 nanowires via a novel stirring hydrothermal process. Compared with conventional hydrothermal reaction , one-dimensional (1D) lead-free BaTiO 3 nanowires can be realized at an even lower temperature with a shorter dwelling time. Results suggest that the mechanical force-driven stirring process improved the diffusion and surface reaction rate of BaTiO 3 nanocrystal growth in the solution phase, apparently, leading to the growth of the BaTiO 3 nanowires via an oriented attachment mechanism. Meanwhile, to the best of our knowledge, this method is also the first reported protocol which is capable to grow elongated BaTiO 3 nanowires with length up to tens of micrometers. This research outcome provides a promising option for low cost, high-throughput fabrication of 1D nanostructure in respect of mass-manufacturing.
研究领域:
材料科学
·
纳米科技
·
无机合成
·
功能材料
·
铁电材料
✓ 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
·
凝聚态物理
·
功能材料
·
热电转换
·
固态制冷
✓ 已验证
DOI
高影响因子
Small
·
2021
·Vol. 18
·期 8
·2105599
·
IF 13.281
Wuhong Xue,Qitao Jiang,Fakun Wang,Ri He,Ruixue Pang,Huali Yang,Peng Wang,Ruilong Yang,Zhicheng Zhong,Tianyou Zhai,Xiaohong Xu
2D ferroelectrics with robust polar order in the atomic-scale thickness at room temperature are needed to miniaturize ferroelectric devices and tackle challenges imposed by traditional ferroelectrics. These materials usually have polar point group structure regarding as a prerequisite of ferroelectricity. Yet, to introduce polar structure into otherwise nonpolar 2D materials for producing ferroelectricity remains a challenge. Here, by combining first-principles calculations and experimental studies, it is reported that the native Ga vacancy-defects located in the asymmetrical sites in cubic defective semiconductor α‑Ga 2 Se 3 can induce polar structure. Meanwhile, the induced polarization can be switched in a moderate energy barrier. The switched polarization is observed in 2D α‑Ga 2 Se 3 nanoflakes of ≈4 nm with a high switching temperature up to 450 K. Such polarization switching could arise from the displacement of Ga vacancy between neighboring asymmetrical sites by applying an electric field. This work removes the point group limit for ferroelectricity, expanding the range of 2D ferroelectrics into the native defective semiconductors.
研究领域:
材料科学
·
凝聚态物理
·
纳米电子学
·
功能材料
·
半导体物理
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Haisheng Chen,Wenwen Chen,Jiaying Shen,Xiaona Du,Tianhong Zhou,Zhengang Dong,Taiyu Bian,Jiaxing Guo,Yiyang Wen,Yuanlin Liang,Zhenping Wu,Yang Zhang
Developing smart luminescent materials with desirable and tunable characteristics has always been an overriding priority of fluorescence technology. However, huge challenges encompass the single functionality of the luminescent materials and the traditional chemical synthetic techniques with rigorously controlling over the miscellaneous experimental conditions and variables. Herein, the lanthanide-doped bismuth-layered ferroelectric (Na 0.5 Bi 0.5 ) 0.96 Er 0.04 Bi 2 Nb 2 O 9.02 has been prepared to be utilized as a platform that not only serves the in-situ and reversible tailoring of the upconverted emission via physical methods, but also enable the versatile functionalities such as photomemory and multi-modal temperature sensing. High luminescent contrast that can reach up to 83.7 % before and after the 405 nm irradiation has been realized on the basis of the photochromic phenomenon of the as-prepared (Na 0.5 Bi 0.5 ) 0.96 Er 0.04 Bi 2 Nb 2 O 9.02 sample, and the fundamental application in the photomemory has been exhibited. Moreover, the performances of triple-mode thermometry built on the fluorescent intensity ratio techniques ( 2 H 11/2 / 4 S 3/2 and 4 S 3/2 / 4 F 9/2 ) as well as the lifetime of the 4 S 3/2 excited state of the Er 3+ ion have been investigated in carefulness, with the maximal relative sensitivities of 1.22 % K −1 at 300 K, 0.92 % K −1 at 510 K, and 0.18 % K −1 at 450 K, respectively. Our results provide significant insights into the methodology of physically modulating the upconversion luminescence, and offer a glamorous pathway for multifunctional high-end applications.
研究领域:
材料科学
·
光学工程
·
功能材料
·
纳米光子学
·
传感技术
·
固态物理
·
智能材料
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2015
·Vol. 41
·期 4
·5498-5504
·
IF 2.605
Shizhou Pu,He Zheng,Zhenlian Chen,Meiya Li,Zhongqiang Hu,Jianbo Wang,Huamin Zou
The microstructures of Bi 0.85 Nd 0.15 FeO 3 ceramics were investigated by using transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), convergent-beam electron diffraction (CBED) and X-ray energy dispersive spectrometry (EDS). The superstructure phase related to 1/4( hh 0) p and 1/4(00 l ) p diffraction spots were observed in the samples. It is found that the superstructure phase can co-exist with R 3 c phase in a single grain. The bright and dark field images accompanied with SAED patterns provided evidences of the superstructure phase dispersed into the matrix with R3c symmetry and evolution of the domain. The ferroelectric domain wall was observed according to the displacement of Fe 3+ ions respect to Bi 3+ sub-lattice in the ferroelectric R 3 c phase based on HRTEM observations. The space group Pnam of the superstructure was identified by combining SAED and CBED techniques . EDS measurement revealed that the concentration of Nd in the Pnam phase is higher than that in R 3 c phase. This might mean that the transition from R 3 c to Pnam structure is due to the inhomogeneous distribution of the Nd concentration and the weakened stereochemical activity of Bi 3+ lone electron pair, arisen from the increase in Nd content.
研究领域:
材料科学
·
凝聚态物理
·
功能陶瓷
·
电子显微学
·
铁电材料
·
多铁材料
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
·Vol. 47
·期 5
·6842-6847
·
IF 3.83
Shunjin Xiong,Rongxia Huang,Congfei Peng,Yejing Dai,Jiajiu Li,Wen Bai,Hua-Tay Lin
A series of HfO 2 -modified (Bi 0 .475 Na 0 . 405 K 0 . 055 Li 0.015 ) 0.95 Ba 0 . 05 Ti (1- x ) Hf x O 3 ( x = 0–0.015) lead-free ceramics were prepared. Results of detailed characterizations showed that the addition of HfO 2 had little influence on the grain size, and all of the samples showed the pure perovskite structure. As the Hf 4+ content increases, the samples changed from the normal ferroelectric phase to the ergodic relaxor state at room temperature, and the ceramics with x = 0.01 showed a high electro-strain of 0.295% at 6 kV/mm. Therefore, this study provides a new insight into of how the HfO 2 addition influences the ferroelectric property of the BNT-based ceramics by B-site substitution.
研究领域:
材料科学
·
无机非金属材料
·
功能陶瓷
·
铁电材料
·
压电材料
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·Vol. 50
·期 23
·51642-51649
·
IF 5.1
Ruifeng Yao,Yongbin Liu,Jingzhe Xu,Jiaxin He,Ming Wu,Lisheng Zhong,Jinghui Gao,Xiaojie Lou
Advanced ferroelectrics with a combination of large piezoelectric response and good temperature stability are crucial for high sensitivity and reliability in sensing and actuating devices. However, these two key factors usually do not cooperate with each other especially for lead-free piezoelectric materials , while achieving high piezoelectricity is normally accompanied by poor stability or vice versa. Herein, we report an approach to resolve the incompatibility between piezoelectric coefficient and temperature stability by designing laminated compositions and controlling element diffusion at multi-interfaces, leading to giant piezoelectricity ( d 33 ∼450 pC/N) with a minimal variation of about 7 % over a wide temperature range (25°C–90 °C), exceeding the classical lead-free systems. By elaborately modulating the diffusion conditions, the concentration of the element shows a gradually change across the laminated structure , contrast to the terraced distribution of element concentration in traditional laminated structure. Further structure characterization clarifies that the gradually change element concentration contributes to a smooth evolution of crystal structure, which is beneficial for the transition of domain switching between different composition layers, resulting in the improvement of piezoelectric temperature stability. The piezoelectric accelerometer manufactured by modulated ceramics was tested by a vibration system and turned out to be temperature stable compared with commercial PZT-4 sensor. This finding provides an effective and straightforward approach for developing superior ferroelectrics with enhanced temperature stability and high piezoelectric coefficient, promising the potential applications of piezoelectric devices concurrently approaching exceptional sensitivity and thermal reliability.
研究领域:
材料科学
·
铁电材料
·
压电器件
·
固体物理
·
陶瓷工程
✓ 已验证
DOI
高影响因子
ACS Photonics
·
2018
·
IF 6.88
Fengren Cao,Wei Tian,Meng Wang,Liang Li
The hybrid organic–inorganic perovskites have been considered as promising candidates for high-performance photodetectors. However, how to fabricate self-powered broadband perovskite photodetectors with tunable photoresponse is still challenging. Herein, we design, for the first time, a ferroelectric semiconductor SrTiO3 (STO) and perovskite film hybrid structure based photodetector. After applying appropriate poled bias, the hybrid photodetector exhibits higher responsivity and faster response speed as compared to an unpoled device and a device without an STO ferroelectric interlayer. By optimizing the STO interlayer density, the positively poled photocurrent and response speed are enhanced to 0.956 mA and 0.1 s at zero bias, respectively. The corresponding responsivity is as high as 0.73A/W at a wavelength of 550 nm, which is much higher than that of the device without an STO interlayer. The improved performance is attributed to the fact that positively polarized STO layers can provide a built-in potential and promote the band bending at the semiconductor surface to facilitate the separation and transportation of the photogenerated charge carriers. Our work provides a promising route to design high-performance ferroelectric–perovskite photodetectors.
研究领域:
光电子学
·
材料科学
·
半导体器件
·
铁电材料
·
光子学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2022
·
IF 10.383
Letao Yang,Xi Kong,Qi Li,Yuan-hua Lin,Shujun Zhang,Ce-wen Nan
Lead-free relaxor ferroelectric ceramics are potential for energy storage applications due to their comprehensive energy storage properties. However, the energy efficiency of many relaxor ceramics is not high enough, leading to high Joule heat during the charge–discharge cycles, thus lowering their energy storage performance. In this work, tantalum (Ta) dopants were introduced into sodium niobate-based relaxor ceramics to improve the resistivity and energy efficiency. The leakage current was reduced by Ta doping, especially at the high electric field. The enhanced resistivity is attributed to the increased bandgap induced by Ta doping. The impedance spectroscopy shows that both the grain and grain boundary resistivities are improved in the high temperature region. As a result, the optimal recoverable energy density and energy efficiency are 6.5 J/cm3 and 94% at 450 kV/cm, respectively. In addition, the energy storage properties exhibit satisfactory temperature stability and cycling reliability. All these merits demonstrate that the Ta modified sodium niobate-based relaxor ceramic a potential candidate for high-power energy storage applications.
研究领域:
材料科学
·
陶瓷与复合材料
·
能量存储
·
铁电材料
·
电子材料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）