CERAMICS INTERNATIONAL
·
2018
·
IF 3.057
Weiwei Yang,Peng Li,Feng Li,Xing Liu,Bo Shen,Jiwei Zhai
In this study, 0.5 wt% MnO 2 doped (0.99- x )(K 0.5 Na 0.5 )(Nb 0.965 Sb 0.035 )O 3 –0.01CaZrO 3 - x (Bi 0.5 K 0.5 )(Hf 0.98 Ti 0.02 )O 3 [abbreviated as (0.99- x )KNNS-0.01CZ- x BKHT, x = 0.01, 0.02, 0.03, 0.04, 0.05, 0.06] lead-free piezoelectric ceramics were fabricated by traditional solid-state reaction method. The microstructure, phase transformation, electromechanical properties and the thermal stability of the ceramics were systematically studied. Resulting from the R-T phase coexisting, a large piezoelectric coefficient ( d 33 ~ 425 pC/N), planar electromechanical coupling factor ( k p ~ 49%) were achieved in the ceramics with x = 0.04. Furthermore, the specimens with x = 0.04 also exhibit excellent temperature stability for d 33 which was manifested by the less than 10% variation of d 33 values when the annealing temperature increase from 25 °C to 100 °C. The good comprehensive properties indicate that MnO 2 doped (0.99- x )KNNS-0.01CZ- x BKHT ceramics are promising candidates for practical application to eliminate the Pb-based piezoelectric ceramics from the market.
研究领域:
材料科学
·
物理学
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2023
·Vol. 58
·期 16
·7076-7091
·
IF 4.5
Jiang Bangqi,Yan Genghua,Xiao Yao,Yuan Ye,Zhao Chuanxi,Mai Wenjie,Hong Ruijiang
All-inorganic Cs 2 AgBiBr 6 film is one of most promising materials in the perovskite family for long-term daily life photodetection applications, due to its fairly nice stability and lead-free nontoxic property. However, high annealing temperature (> 250 °C) process is widely used and low temperature synthesis of high-quality Cs 2 AgBiBr 6 is still a big challenge, which limits the development toward flexible device. Herein, we developed a Mn doping solution route for Cs 2 AgBiBr 6 perovskite which is the first reported element doping process that can effectively improve the film quality under low annealing temperature. The corresponding flexible photodetectors exhibit favorable self-power characteristics and satisfying photoelectric performance with high detectivity of > 10 10 Jones, μs level response speed and large LDR over 110 dB. Such good performance can be maintained even at 120 °C fabrication process. The material properties, device performances and doping mechanism are systematically discussed in the paper. To our knowledge, this is one of the lowest temperature fabrication processes for high performance flexible Cs 2 AgBiBr 6 devices. Our results suggest a feasible method and indicate the promising application of Cs 2 AgBiBr 6 films for flexible photovoltaic devices.
研究领域:
材料科学
·
光电技术
✓ 已验证
DOI
高影响因子
Exploration
·
2024
·
IF 0
Heng Guo,Linlin Shi,Zengliang Shi,Yue He,Yizhi Zhu
Yellow light-emitting diodes (LEDs) with a wavelength of 570–590 nm can reduce the excitability of peripheral nerves and the sensitivity of the skin, stimulate collagen synthesis, and tighten the skin, which plays an important role in skin rejuvenation. In general, commercial LEDs are made of phosphor excited by ultraviolet chips. It is very important for the development of yellow light emitters with high luminous efficiency, good stability, and environmental protection. For the first time, a simple organic structural unit (2-methylimidazole, 2-MIM) was used to collect a mixture of two metal precursors (CsI and CuI) and successfully synthesized an all-inorganic lead-free yellow light CsCu 2 I 3 powder in water. The prepared CsCu 2 I 3 powder exhibited excellent optical properties and considerable stability. Finally, a phosphor-converted LED (pc-LED) device was fabricated via the CsCu 2 I 3 phosphor coated on a 310 nm ultraviolet chip. The pc-LED device's electroluminescence spectra may be a good fit for the blood's absorption regions. Therefore, this work provides a facile method for the synthesis of novel lead-free metal halide CsCu 2 I 3 powder in eco-friendly solvents. In addition, the stable and efficient CsCu 2 I 3 powder shows promising exciting potential applications in photoluminescence and phototherapy fields.
研究领域:
材料科学
·
光学
·
生物医学工程
✓ 已验证
DOI
JOURNAL OF ALLOYS AND COMPOUNDS
·
2021
·
IF 5.316
Sheng-Guo Lu,Xiongwei Lin,Jiang Li,Dandan Li,Yingbang Yao,Tao Tao,Bo Liang
The electrocaloric effect (ECE) in lead-free (Ba 1−x Sr x )(Sn 0.05 Ti 0.95 )O 3 (BSSnT) (x = 0.05, 0.10, 0.15, 0.20) ceramics were investigated around room temperature using direct and indirect approaches. Results indicate that the maximum ECE occurs near the Curie temperature and slightly shifts towards high temperatures with the increasing applied electric field. The directly measured ECE is larger than that calculated using the Maxwell relation. The maximum electrocaloric strength ΔT/ΔE = 0.52 × 10 −6 K m/V was obtained at T = 36 °C, with an adiabatic ΔT of 1.05 °C at 2 MV m −1 . An analytic formula of electrocaloric strength (dT/dE) was deduced, via which the maximum dT/dE was estimated. The factors affecting the electrocaloric strength were discussed, and the experimental results were compared with those derived from the formula.
研究领域:
材料科学
·
物理学
✓ 已验证
DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2024
·Vol. 107
·期 10
·6833-6843
·
IF 3.5
Hailan Qin,Jianwei Zhao,Xiaoxin Chen,Hongtian Li,Shenghao Wang,Yuxiao Du,Ahmad Azmin Mohamad,Huanfu Zhou,Dawei Wang
The investigation of lead-free ceramics with exceptional piezoelectric properties holds great importance in the substitution of lead-based materials, hence promoting the development of green technology and fostering an environmentally sustainable society. This study successfully synthesized two series of Bi(Mg 2/3 Nb 1/3 )O 3 (BMN)-modified BiFeO 3 –BaTiO 3 (BF–BT) lead-free piezoelectric ceramics using the conventional solid-state reaction approach. The phase structure, microstructure, dielectric, and piezoelectric properties of these ceramics were comprehensively investigated. A typical perovskite structure is observed in all probed compositions, and the associated phase structure undergoes a gradual transition from a rhombohedral-cubic phase mixture to a cubic-dominant phase structure as increases the content of BMN and BT. All compositions exhibit obvious core–shell microstructures with inhomogeneous element distributions. Most importantly, the BF–0.30BT–0.005BMN and BF–0.34BT–0.03BMN piezoelectric ceramics presented remarkable values for the piezoelectric coefficient (225 pC/N) and converse piezoelectric coefficient (396 pm/V), respectively. These findings highlight the potential of BMN-modified BF–BT ceramics for use in high-performance piezoelectric applications.
研究领域:
材料科学
·
物理学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Xinyu Chen,Xinyu liu,Taotao Ai,Qian Qiu,Minghui Hao,Yang He,Minghui He,Haoyu Wang,Chunlin Song,Daniel Q. Tan,Gang Liu,Yan Yan
Herein, a series of lead-free ceramics, (1− x )(0.78Bi 0.5 Na 0.5 TiO 3 –0.22SrTiO 3 )– x Ba(Zr 0.5 Ti 0.5 )O 3 (abbreviated as BNST–BZT), were synthesized via the conventional solid-state reaction approach. The effects of introducing the BZT component on the electromechanical transformation properties and phase transition of BNST were thoroughly investigated, leading to the development of a corresponding phase diagram. The addition of BZT significantly influenced phase transitions and domain structures, with phase coexistence involving ferroelectric rhombohedral and relaxor tetragonal phases. XRD analysis and temperature-dependent measurements of dielectric and ferroelectric properties demonstrated that the relaxor phase content could be modulated by adjusting the BZT content and varying the temperature. Domain changes were also observed through PFM testing. With the addition of BZT, the RE-FE phase transition temperature T F-R is successfully adjusted to near room temperature, accompanied by the disruption of long-range ferroelectric domains and the formation of polar nanoregions. This transition marks a shift from NR to ER state. Specifically, with an optimized BZT content of 0.006, the material demonstrates a significant strain of 0.41 % under a 70 kV/cm and achieves a maximum normalized strain of 715 p.m./V at 50 kV/cm. This research introduces an effective doping strategy that offers valuable insights into the design and development of high-performance lead-free ceramics. Additionally, it investigates the mechanisms underlying the observed high strain responses, highlighting their potential application in lead-free piezoelectric actuators.
研究领域:
材料科学
·
无机非金属材料
·
功能陶瓷
✓ 已验证
产品关联
DOI
高影响因子
Journal of Semiconductors
·
2025
·Vol. 46
·期 5
·052803
·
IF 5.3
Ziyu Cai,Junchi Zhu,Chenyuan Ding,Tao Dong,Boyang Yu,Wenzheng Hu,Jiayi Xie,Feng Ye,Qiufeng Ye,Zebo Fang
Owing to their low toxicity and remarkable stability, perovskites based on antimony and bismuth have garnered significant interest in recent years. However, A3B2X9 perovskite materials derived from antimony and bismuth face several challenges, including excessively wide band gaps, elevated defect densities, and suboptimal film quality, all of which hinder advancements in device efficiency. While extensive studies have been undertaken to investigate the effects of modulating the A-site and X-site elements in lead-free A3B2X9 perovskites, there remains a notable scarcity of reports addressing the impact of modifications to the B-site element. In this study, we investigated the alloying of antimony and bismuth within the 2D Cs3B2I6Br3 perovskite. By systematically varying the ratios of two elements, we found that the incorporation of both antimony and bismuth at the B-site significantly enhances the quality of the perovskite films. Our findings indicate that a 1 : 1 ratio of antimony to bismuth produces the densest films, the highest photoluminescence intensity, and superior photovoltaic performance. Ultimately, the devices fabricated using this optimal ratio achieved an open-circuit voltage (VOC) of 1.01 V and a power conversion efficiency (PCE) of 0.645%.
研究领域:
材料科学
·
能源工程
✓ 已验证
产品关联
DOI
高影响因子
Advanced Science
·
2025
·
IF 14.1
Guang Wang,Jiongzhi Zheng,Jie Xue,Yixin Xu,Qiye Zheng,Geoffroy Hautier,Haipeng Lu,Yanguang Zhou
Lead-free halide double perovskites provide a promising solution for the long-standing issues of lead-containing halide perovskites, i.e., the toxicity of Pb and the low stability under ambient conditions and high-intensity illumination. Their light-to-electricity or thermal-to-electricity conversion is strongly determined by the dynamics of the corresponding lattice vibrations. Here, the measurement of lattice dynamics is presented in a prototypical lead-free halide double perovskite(Cs 2 NaInCl 6 ). The quantitative measurements and first-principles calculations show that the scatterings among lattice vibrations at room temperature are at the timescale of ≈1 ps, which stems from the extraordinarily strong anharmonicity in Cs 2 NaInCl 6 . Further the degree of anharmonicity of each type of atom is quantitatively characterized in the Cs 2 NaInCl 6 single crystal, which stems from the interatomic forces, and demonstrate that this strong anharmonicity is synergistically contributed by the bond hierarchy, the tilting of the NaCl 6 and InCl 6 octahedral units, and the rattling of Cs + ions. Consequently, the crystalline Cs 2 NaInCl 6 possesses an ultralow thermal conductivity of ≈0.43 W mK −1 at room temperature, and a weak temperature dependence of T −0.41 . These findings uncovered the underlying mechanisms behind the dynamics of lattice vibrations in double perovskites, which can largely benefit the design of optoelectronics and thermoelectrics based on halide double perovskites.
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Meixia Wu,Xiao Zhou,Xihui Liang,Yifeng Han,Yonghong Li,Xingan Jiang,Xueyun Wang,Yisheng Chai,Xiang Zhou,Hui Yang,Dan Lin,Ping Xu,Man-Rong Li
Multifunctional thermochromic materials integrated optical, ferroelectric, and/or magnetic properties have been long envisioned and played an invaluable role in signal processing and non-contact optical information storage in smart windows. However, poor materials stability, together with high discoloration temperature, absence of ferroelectric, or magnetic behaviors, impedes most thermochromic materials for practical applications. Here, the thermochromic behavior of all-inorganic lead-free ferroelectric Sn 2 P 2 S 6 (SPS) is extensively studied, which exhibits a reversible color change between light orange and red around the ferroelectric-paraelectric phase transition temperature (∼ 67 °C). In situ powder X-ray diffraction (PXRD) and Raman spectroscopy indicate the change of P-S and Sn-S bond distance, and thus result in the modification of (P 2 S 6 ) octahedral geometry and the coordination environment of Sn 2+ ions along with the evolution of thermochromism (TCM). Additionally, the first-principles calculations reveal that, the Sn 5 s 2 stereochemically active lone pair electrons evoke negative lattice expansion comparable to that of the known ZrW 2 O 8 at warming and is responsible for the reversible TCM of SPS. SPS also possesses high near-infrared reflectance ( R > 80 %, 1100-2500 nm). The integration of ferroelectricity, high near-infrared reflectance, and TCM below 100 °C renders potential applications of the titled compound in multifunctional optical smart windows.
研究领域:
材料科学
·
光学
·
物理化学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Changshuai Shu,Jiachen Xi,Chongyang Li,Wangfeng Bai,Peng Zheng,Peng Li,Jiwei Zhai
Constructing relaxor ferroelectrics (RFEs) in dielectrics is an efficient approach to break the so-called inverted relations between recoverable energy storage density ( W rec ) and efficiency ( η ). However, in view of the requirement for energy conservation, the major challenge of realizing near-zero energy consumption (ultrahigh η ) accompanied with high W rec still remains in the field of dielectric energy storage. Here, we designed a linear-like RFE with directly induced short-range local polar nanoregions via incorporating the ferroelectric into linear dielectric to realize high-performance capacitive storage, especially near-zero energy loss. Benefiting from linear-like RFE design, the combination of enhanced breakdown strength, ultrasmall dielectric loss, and minimized polarization hysteresis synergistically contributes to a record-high η of ∼97.7 % with a high W rec of 5.87 J/cm 3 and ultrahigh figure of merit of 255, which is ahead of most recently reported state-of-the-art lead-free ceramics. Moreover, based on such linear-like RFE merits, high thermal/frequency stability and cycling durability with high η > 90 % of the designed ceramics expand their applications in harsh condition energy storage systems. This study demonstrates the superiority of linear-like RFE design and provides a referential paradigm towards developing advanced near-zero energy loss energy storage dielectrics.
研究领域:
材料科学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
SENSORS AND ACTUATORS A-PHYSICAL
·
2024
·
IF 4.1
Chengxu Lin,Chenyu Li,Rui Liu,Xuning Zhang,Xingyue Liu,Bo Sun,Tielin Shi,Zhiyong Liu,Guanglan Liao
The perovskite scintillators have been extensively studied recently for their merits of tunable emission spectra and simple preparation processes. However, the practical applications of perovskite scintillator-based X-ray image sensor are still impeded by inadequate radioluminescence, poor environmental stability, and low imaging resolution. Herein, we demonstrate a scalable co-firing method to fabricate high-quality lead-free Cs 3 Cu 2 I 5 perovskite scintillator and an Indium (In)-doping strategy is introduced to enhance its radioluminescence performance at the same time. The In-doped Cs 3 Cu 2 I 5 obtains a high PLQY of 77.9% and a relative light output of 53372 ph/MeV, which are 0.34 and 1.08 times higher than those of the undoped counterpart, respectively. The X-ray detection limit of the In:Cs 3 Cu 2 I 5 can reach 150.55 nGy air /s, 36.53 times lower than the requirement for X-ray medical diagnosis. The synthesized scintillator also shows superior stability under continuous high dose X-ray irradiation of 6800 μGy air /s for 120 minutes, maintaining 95% of its initial radioluminescence intensity. Furthermore, a large-area (300 cm 2 ) flexible perovskite scintillator film is prepared, which owns a much competitive resolution of 10 lp/mm and less distortion in X-ray imaging. This work provides a practical path for the wide application of perovskite scintillator in the field of X-ray detection and imaging in near future.
研究领域:
材料科学
·
医学影像
·
放射学
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Energy
·
2019
·
IF 0
Jingwei Xiu,Yangfan Shao,Linxun Chen,Yue Feng,Junfeng Dai,Xusheng Zhang,Yi Lin,Yudong Zhu,Zhenggang Wu,Yini Zheng,Hui Pan,Chang Liu,Xingqiang Shi,Xin Cheng,Zhubing He
Owning the merits of both lead-free and air-stable, the double-perovskite Cs 2 AgBiBr 6 has attracted increasing attention, but suffers low visible-light absorption coefficient due to its large indirect bandgap. Moreover, the electronic structure of its synthesized films has not been explored clearly yet. In this work, we developed a general and promising method to fabricate continuous, uniform and highly orientated Cs 2 AgBiBr 6 films in large scale on various substrates through capillary-assisted dip-coating method. Strikingly, those optimized films are single crystalline verified by φ-scan XRD . Its electronic structure was carefully studied independently by multi-photo-physical characterizations. Its bandgap can be tuned from 2.65 to 2.25 eV by changing the substrate temperature in growth from 40 to 160 °C. Essentially, their work-function (WF) was determined at −5.01 eV and WF-VBM is around 2 eV. This novel band structure with typical n-type characteristic, was further confirmed by DFT calculations, which reveals that the Cs interstitials and Br vacancies derived deep defect levels were fixed around its Fermi level, closer to the conduction band. This conclusion is different from its widely accepted p-type feature, but definitely deepens our understanding of this material and inspires us to find more valuable strategies of modulating its band structure and optoelectronic properties.
研究领域:
材料科学
·
光电化学
✓ 已验证
DOI
危险品化学品经营许可证（带存储）