JOURNAL OF ALLOYS AND COMPOUNDS
·
2023
·
IF 6.2
Shiyi Zhang,Mengdi Cheng,Yangxi Yan,Zhimin Li,Pangpang Wang,Ri-ichi Murakami,Dongyan Zhang
High-performance piezoelectric materials , whose displacement is sensitive to an external field and vice versa, are constantly required in electromechanical applications. Here, we introduce Nd 3+ ions into 0.49Pb(Nb 2/3 Ni 1/3 )O 3 -0.51Pb(Hf 0.3 Ti 0.7 )O 3 (PNN-PHT) ceramics via the solid-state method. By constructing a ferroelectric system in the morphotropic phase boundary region and exploiting the synergistic effect of polar nanoregions and an enhanced local structural heterogeneity, excellent piezoelectricity and dielectric properties are obtained. The optimized piezoelectric coefficient d 33 , dielectric constant ε 33 , electromechanical coupling factor k p , and dielectric loss tanδ are 1125 pC/N, 8667, 0.66 %, and 1.94 %, respectively. The Vogel-Fulcher law and relaxation analysis were adopted to understand the origin of the high piezoelectricity. The Rayleigh analysis method was used to study the intrinsic and extrinsic contributions to the piezoelectricity of the Nd-doped PNN-PHT ceramics, the extrinsic contribution was found to be up to 19 % in the optimal region (PNN-PHT + 0.4 at. % Nd 2 O 3 ). Moreover, according to in-situ ferroelectric measurements and fatigue measurements, the PNN-PHT + 0.4 at. % Nd 2 O 3 ceramic exhibits excellent fatigue resistance and stable piezoelectric behavior at 60 ℃ . This work provides an approach to realize high-performance piezoelectric ceramics with good electromechanical stability under external condition, which is expected to expand the range of application of piezoelectric materials, e.g., for transducers.
研究领域:
材料科学
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电陶瓷
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压电材料
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铁电材料
✓ 已验证
DOI
高影响因子
MINERALS ENGINEERING
·
2025
·
IF 5
Yubo Ge,Hualing Zhao,Guiqing Zhang,Qinggang Li,Shengxi Wu,Zhiyong Gao
In previous work, we developed an H 2 SO 4 -Fe 2 (SO 4 ) 3 roasting and water leaching method to leach rare earth elements (REEs), niobium (Nb), and titanium (Ti) from a low-grade concentrate mixture of the Baerzhe ore deposit in China ( Ge et al., 2024 ). However, conventional chemical precipitation and fluorine-ligand extraction methods for separating REEs/Nb/Ti in the leach solution face challenges, including co-precipitation of REEs and Nb/Ti, low recovery efficiency, and significant environmental concerns. To address these issues, a novel two-step solvent extraction process for efficient separation and recovery of Nb and Ti from leach solution was proposed in this work. The quaternary ammonium salt extractant (N263-CO 3 2- ) was employed to selectively co-extract Nb and Ti from the leach solution for achieving effective separation them from REEs. The resultant Nb(OH) 5 /Ti(OH) 4 precipitates were dissolved in H 2 C 2 O 4 -H 2 SO 4 mixture for selective extraction of [NbO(C 2 O 4 ) 2 - ] using tri-n-octylamine (TOA). The extraction mechanism confirmed that N263 preferentially extracts Nb/Ti via anion exchange, with the primary contribution from N263-CO 3 2- to Nb/Ti extraction, followed by N263-SO 4 2- , while protonated TOA selectively extracts [NbO(C 2 O 4 ) 2 - ] through anion–cation association. Ultimately, the recovery efficiencies of Nb and Ti reached 96.0 % and 69.0 %, respectively, producing Nb 2 O 5 (99.6 %) and TiO 2 (99.2 %), with REEs losses < 0.5 %. This study offers a novel approach for the efficient selective separation and recovery of Nb/Ti from leach solution.
研究领域:
冶金学
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材料科学
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化学工程
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2015
·
IF 2.999
Y. Lu,S. Khan,C.L. Song,K.K. Wang,G.Z. Yuan,W. Li,G.R. Han,Y. Liu
The column-structured Nb-doped TiO 2 (TNO) films with various Nb concentrations in the range between 0 and 10 at.% have been prepared by a sol–gel method. The phase compositions, element concentrations, microstructures, and optical-electron properties have been characterized by using X-ray diffraction, X-ray photoelectron spectroscopy, electron microscopy , and UV/Vis/Near-IR spectrophotometer. The experimental results show that all of the samples prepared in the present work exhibit column-structured morphology and Nb doping concentration has a non-monotonic effect upon the microstructure. The relatively low conductivity and high transmittance of the samples demonstrate that column-structured microstructures greatly improve the optical and electronic properties of TNO films. The favorable sample with 10 at.% Nb doping concentration exhibits a resistance of about 2.27 Ω cm and transmittance of approximately 68.78% with 85 nm thickness.
研究领域:
材料科学
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纳米技术
✓ 已验证
DOI
高影响因子
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
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2021
·
IF 3.995
Panpan Xu,Yupeng Wang,Wentao Hao,Li Sun,Ensi Cao,Yongjia Zhang
TiO 2 ceramics co-doped with In and Nb exhibit unusual large dielectric-permittivity phenomena, but their sintering temperature is essentially higher than 1400 °C and the holding time is usually longer than 5 h, which is very uneconomical for industrial production and practical applications. Therefore, to maintain the relatively good dielectric properties of In and Nb co-doped TiO 2 ceramics and reduce the sintering temperature to about 1300 °C, B 2 O 3 , was added as a sintering aid to prepare B 2 O 3 /(In 0.5 Nb 0.5 ) 0.05 Ti 0.95 O 2 ceramics in this paper. The crystalline structures, microstructures, and electrical properties were investigated and discussed. The results showed that the sintering temperature of B 2 O 3 /(In 0.5 Nb 0.5 ) 0.05 Ti 0.95 O 2 ceramics indeed prominently decreased, but their dielectric loss was relatively large, possibly caused by the pores left following B 2 O 3 volatilization.
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
Journal of Materials Chemistry C
·
2023
·Vol. 11
·期 35
·11895-11904
·
IF 6.4
Mengdi Cheng,Yangxi Yan,Zhimin Li,Pangpang Wang,Ri-ichi Murakami,Dongyan Zhang
Modern electronic devices are highly in demand for high-performance piezoelectric materials. Herein, Pb(Ni, Nb)O3–Pb(Lu, Nb)O3–PbTiO3 piezoelectric ceramics are investigated, among which the 0.52PNN–0.16PLN–0.32PT ceramic shows the best performance (d33 = 850 pC N−1, d33* = 1139 pm V−1). Excellent piezoelectricity can be explained by multiphase coexistence, as well as an enhanced local heterogeneous structure. Polar nanoregions that promote polarization rotation are an important cause of high piezoelectricity according to characterization using SEM and PFM. TEM also confirmed a heterogeneous domain configuration with two coexisting phases. In addition, a large signal piezoelectricity of 1000 pm V−1 is maintained in the temperature range of 20–90 °C. This work presents an excellent example of achieving both high piezoelectric properties and a good temperature range in relaxor ferroelectric ceramics.
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
CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Xingke Zheng,Aochen Du,Yun Ye,Enguo Chen,Sheng Xu,Tailiang Guo
Amidst growing concerns for environmental sustainability and green ecology, the utilization of Light Emitting Diodes (LEDs) for indoor plant cultivation has emerged as an influential area of research. Nonetheless, the growth of indoor plants is often constrained by inadequate lighting. Consequently, designing novel LEDs to create an appropriate light environment has emerged as a focal point in research. As a new type of photocatalytic material with excellent optical properties and light stability, double perovskite has broad application prospects in LEDs manufacturing. In this context, this article aims to synthesize a new Ca 2 Lu(Nb,Mn)O 6 double perovskite and study its optical properties in LEDs lighting for indoor plant growth. A new Ca 2 Lu(Nb,Mn)O 6 double perovskite were synthesized using the traditional high-temperature solid-phase method. The crystal structure and luminescence properties of the double perovskite were characterized in detail using powder X-ray diffraction (XRD), Rietveld refinement , excitation and emission spectra, decay lifetimes, quantum efficiency (QE), electron paramagnetic resonance (EPR) spectra, temperature-dependent emission spectra, and the Commission International de l’Eclairage (CIE) color coordinates. The photoelectric properties of Ca 2 Lu(Nb,Mn)O 6 and Ca 2 LuNbO 6 double perovskite have been explored through first-principles investigations. The absorption spectra from 270 to 600 nm indicates that it can be effectively excited by ultraviolet (UV) light. The emission spectra show a strong broad red emission peak at 684 nm. The luminescence mechanism has been studied using the Tanabe-Sugano diagram. In addition, the internal UV emission ratio β 1 , crystal field strength D q , and Racah parameters B and C were evaluated. The thermal stability of the sample was studied through emission spectra at heating temperatures from 303 to 573 K. The results indicate that Ca 2 Lu(Nb,Mn)O 6 double perovskite provides a new solution for indoor plant growth.
研究领域:
材料科学
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光学工程
·
植物学
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2024
·
IF 3.8
Jingxu Liu,Yanning Ren,Yi Zhao,Haoyun Zhou,Xiaohui Liu,Yong Guo,Yanqin Wang
The hydrotreatment of fats and oils for biofuel synthesis significantly contributes to carbon emission mitigation. Conventionally, this process necessitates a bifurcated pathway encompassing hydrodeoxygenation (HDO)/decarboxylation (DCO) and subsequent isomerization reactions. In this research, we synthesized a niobium-doped bifunctional catalyst, denoted as Pt/AlSiO-Nb, capable of concurrently executing HDO and isomerization of palm oil. Our examination of the palm oil hydrotreatment network, with palm acid and tripalmitin as representative model compounds, revealed that the oil undergoes hydrolysis to form fatty acids and then undergoes deoxygenation to n-alkanes via HDO or DCO routes, succeeded by n-alkane isomerization, where cracking reactions also transpire. Comprehensive characterizations of the catalyst delineated that niobium incorporation markedly augments the support–platinum interaction and proliferates the catalyst’s medium and weak acid sites, culminating in enhanced HDO and isomerization performance. These insights herald a novel methodology for biofuel generation from fats and oils, offering a streamlined approach to their catalytic transformation.
研究领域:
催化化学
·
可再生能源
✓ 已验证
DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2025
·
IF 3.8
Yi-Ning Huang,Mengyan Liu,Chenyang Ye,Huajie Luo,Ji Zhang,Dmitry V. Karpinsky,Shan-Tao Zhang,Yaojin Wang
Ceramic-based dielectric capacitors have gained prominence in research owing to their high relative permittivity, excellent mechanical properties, and temperature stability. BiFeO 3 -based ceramics have captured significant attention in dielectric capacitors attributable to their high saturation polarization. Yet, the high remanent polarization, as well as the low electric breakdown strength, constrains the improvement of their energy storage performances. Herein, we incorporated the A-/B-site complicated component (La 0.5 Na 0.5 )(Mg 1/3 Nb 2/3 )O 3 into the binary solid solution 0.7BiFeO 3 –0.3BaTiO 3 ceramics with morphotropic phase boundary, to enhance the endurance for electric field and reduce remanent polarization by optimizing relaxor behavior. Consequently, a high recoverable energy density of 8.3 J/cm 3 and a high efficiency of 84.6% under 500 kV/cm were obtained in the preferred composition. These results offer a feasible pathway to exploit the high-performance BiFeO 3 -based ceramics for electrostatic energy storage.
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
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2023
·
IF 5.7
Lei Zhang,Zheng Cao,Qing-Qiao Fu,Chun-Yu Li,Ya-Qian Du,Yan-Nan Li,Ta La,Dai-Bing Zhang,Jun Wang
Yb 2 Ti 2 O 7 exhibits ferromagnetic and magnetic properties , which are expected to exert a discernible influence on the thermoelectric properties of SrTiO 3 composite. The La-Yb-Nb-doped SrTiO 3 powders, synthesized via the hydrothermal method , were prepressed and then buried in carbon powder before being sintered in a muffle furnace at 1573 K for 5 h. The Yb dopant precipitated during the sintering process, leading to the in-situ formation of Yb 2 Ti 2 O 7 . The content of Yb 2 Ti 2 O 7 increased with an increasing Yb concentration, resulting in a reduction in thermal conductivity and grain boundary potentials, and an increase in the peak electrical conductivity . The La and Nb dopants affect the electrical conductivity and the Seebeck coefficient. Therefore, by controlling the La, Nb, and Yb ratios, the La8Yb2Nb15 sample achieved the largest power factor ( PF ) value of 0.9 mWm −1 K −2 and a low thermal conductivity of 2.9 W m −1 K −1 , resulting in a high ZT value of 0.32 at 1000 K.
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2024
·Vol. 17
·期 24
·6251
·
IF 3.1
Xing-Hua Ma,Qi Qu,Haitao Wu,Zhenlu Zhang,Xingyi Ma
M 2+ N 4+ Nb 2 O 8 -type ceramics (where M = Mg, Ca, Mn, Co, Ni, Zn and N = Ti, Zr) are essential for satellite communication and mobile base stations due to their medium relative permittivity ( ε r ) and high quality factor ( Q × f ). Although ZnTi 0.2 Zr 0.8 Nb 2 O 8 ceramic exhibits impressive microwave dielectric properties, including an ε r of 29.75, a Q × f of 107,303 GHz, and a τ f of −24.41 ppm/°C, its sintering temperature of 1150 °C remains a significant barrier for integration into low-temperature co-fired ceramic (LTCC) technologies. To overcome this limitation, a strategy involving the partial substitution of Zn 2+ with Cu 2+ and the addition of LiF as a sintering aid was devised for ZnTi 0.2 Zr 0.8 Nb 2 O 8 . The dual impact of Cu 2+ partial substitution and LiF as a sintering enhancer facilitated the successful sintering of Cu 0.3 Zn 0.7 Ti 0.2 Zr 0.8 Nb 2 O 8 ceramics at a reduced temperature of 950 °C using the conventional solid-state reaction method. These ceramics exhibited excellent microwave dielectric properties. Notably, Cu 0.3 Zn 0.7 Ti 0.2 Zr 0.8 Nb 2 O 8 ceramic with 40 mol% LiF addition demonstrated optimal microwave dielectric properties without any reaction with a silver electrode at a sintering temperature of 950 °C, yielding ε r = 32, Q × f = 45,543 GHz, and τ f = −43.5 ppm/°C.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2025
·
IF 3.8
Qiqiang Zhang,Lei Cao,Bo Peng,Hui Zhang,Xingyuan San,Yanchun Zhou,Man Jiang,Qingguo Feng,Chunfeng Hu
MAX phase ceramics, as a family of ternary layered ceramics, have received a lot of attention in the past decade due to their potential as precursors for two-dimensional transition metal carbides. However, due to complex multi-component metallurgical reactions, multicomponent MAX phase ceramics have always faced difficulties in purification and homogenization. This paper identifies a new strategy for synthesizing multicomponent MAX phase ceramics that can eliminate these synthesis difficulties. This path utilizes low-temperature (below 1000°C) stable Ti 2 AlC and carbide powder as initial materials to simplify complex multi-component reactions into a one-step reaction, successfully achieving high purity and precise doping ratio. As an example, four novel doped MAX phase ceramics, Ti 2 MAlC 2 (M = Nb, Ta, W) and Ti 2 HEAlC 2 (HE = 1/7Ti, 1/7V, 1/7Zr, 1/7Nb, 1/7Hf, 1/7Ta, 1/7 W) were successfully synthesized using this method. This dynamic-based design, on one hand, simplifies the reaction mechanism to make purification easier, and on the other hand, the concentrated release of entropy during the reaction process promotes phase transition and related element homogenization.
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2017
·
IF 7.504
Xiaodong Ren,Dong Yang,Zhou Yang,Jiangshan Feng,Xuejie Zhu,Jinzhi Niu,Yucheng Liu,Wangen Zhao,Shengzhong Frank Liu
Electron transport layer (ETL), facilitating charge carrier separation and electron extraction, is a key component in planar perovskite solar cells (PSCs). We developed an effective ETL using low-temperature solution-processed Nb-doped SnO2 (Nb:SnO2). Compared to the pristine SnO2, the power conversion efficiency of PSCs based on Nb:SnO2 ETL is raised to 17.57% from 15.13%. The splendid performance is attributed to the excellent optical and electronic properties of the Nb:SnO2 material, such as smooth surface, high electron mobility, appropriate electrical conductivity, therefore making a better growth platform for a high quality perovskite absorber layer. Experimental analyses reveal that the Nb:SnO2 ETL significantly enhances the electron extraction and effectively suppresses charge recombination, leading to improved solar cell performance.
研究领域:
材料科学
·
能源技术
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）