JOURNAL OF MATERIALS RESEARCH
·
2020
·Vol. 35
·期 16
·2230-2238
·
IF 2.502
Zhou Ying,Gan Guoyou,Ge Zhenhua,Feng Jing,Song Peng
HfO 2 –Sm 3 TaO 7 ceramics are prepared through a solid-state reaction method. The X-ray diffraction and structural refinement show that the phase structures of HfO 2 –Sm 3 TaO 7 ceramics are an ordered orthorhombic phase and the space groups are belonging to Ccmm . The degree of the structural disorder increases with increasing HfO 2 content. The solid solution mechanism reveals that Hf 4+ exists in the form of interstitial ions that cause crystal expansion when the doping content is less than 4 mol%. When the doping concentration of HfO 2 ≥ 4 mol%, the Hf 4+ ions can substitute an equal number of Sm 3+ and Ta 5+ ions. The phase transition of Sm 3 TaO 7 ceramics is removed with increasing HfO 2 content, and the 8 mol% HfO 2 –Sm 3 TaO 7 ceramics have a high thermal expansion coefficient of 10.2 × 10 −6 K −1 at 1200 °C. The 2 mol% HfO 2 –Sm 3 TaO 7 ceramics have the lowest thermal conductivity (1.03 W/m K at 900 °C), which is lower than previous research of the 7–8 YSZ. The outstanding thermophysical properties of HfO 2 –Sm 3 TaO 7 ceramics indicate that they are potential thermal-barrier coating materials.
研究领域:
材料科学
·
无机化学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2018
·
IF 3.779
Junlei Qi,Minghe Cao,Yiying Chen,Zichen He,Chen Tao,Hua Hao,Zhonghua Yao,Hanxing Liu
High permittivity materials continue to arouse considerable interest due to their applications in the field of high performance capacitors. However it is still a challenge to make material both with stable high permittivity and low dielectric loss. Here, the Sr 1-3x/2 Ce x TiO 3 (SCT) ceramics are synthesized via solid-state reaction process and sintering in air. The sample (x = 0.01) exhibits a high permittivity of ∼7000 and low dielectric loss of ∼0.007 at room temperature and 1 kHz. Moreover, the dielectric properties are stable over a very broad temperature and frequency range. Further investigations reveal that the high permittivity is related to the defect chemistry caused by the trace Ce ions doping. The Ti 3+ ions substitute the Ti 4+ ions lead to the Ti-O octahedral off-center, which make a certain contribution to improve the permittivity. The low dielectric loss is owing to the fact that the defects are more likely to be in the form of defect clusters in the Ce doped SrTiO 3 monophase solid solutions. The appropriate defect chemistry design suppresses the dielectric loss relaxation peak of Sr 1-x Ce x TiO 3 (x = 0.01) caused by the motion of oxygen vacancies .
研究领域:
材料科学
·
电子材料
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2018
·
IF 3.057
Xingxing Zhou,Minghe Cao,Zhijian Wang,Yun Rao,Qu Luo,Bo Yang,Hua Hao,Zhonghua Yao,Zhiyong Yu,Hanxing Liu
Sr 0.99 Ce 0.01 Ti 1-x O 3 (SCT, x = 0, ± 0.0025, ± 0.0050, 0.0075) ceramics were prepared by solid state reaction methods and sintered in air atmosphere at different temperatures, with a soaking time of 2 h. The dielectric properties of all samples presented excellent temperature independence over a broad temperature range from 25 to 330 ℃ and frequency independence between 10 kHz and 1 MHz. Sr 0.99 Ce 0.01 Ti 0.9925 O 3 (SCT0.9925) ceramics sintered in air atmosphere exhibited a high permittivity (~5400) and a low dielectric loss (~0.01) measured at room temperature and 1 kHz. XPS and complex impedance spectroscopy analysis confirmed that the high permittivity and low dielectric loss were attributed to the fully ionized oxygen vacancies and giant defect-dipoles in Ti-deficient samples. However, a higher dielectric loss of Ti-rich samples is owing to the destruction of giant defect dipoles, in which highly localized electrons were transformed into hopping electrons.
研究领域:
材料科学
·
陶瓷工程
·
电子材料
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2025
·
IF 6.2
Xincheng Cai,Junjing Duan,Zhangyi Huang,Lexing Liang,Zhenyu Zhang,Mao Deng,Jianqi Qi,Tiecheng Lu
Y 2 O 3 MgO composites have emerged as promising mid-infrared (MIR) materials owing to their exceptional broadband transmittance and remarkable thermal stability at elevated temperatures. Nevertheless, the presence of uncontrollable absorption bands within the 4–7 μm spectral range, compromises their optical performance in advanced MIR systems. To address this limitation, we systematically investigated annealing as a strategic approach for modulating defect chemistry in oxide composites. In this paper, the absorption peaks of Y 2 O 3 MgO composites were controlled by varying the annealing conditions. As the annealing temperature increases from 600 °C to 1100 °C, the absorption peaks of Y 2 O 3 MgO composites gradually shift from ∼4.9 μm to ∼6.8 μm, with a transition temperature ∼900°C. This behavior is attributed to the oxidation of metal-organic coordination (MOC) to CO 3 2- in high-temperature air. Ultimately, Y 2 O 3 MgO composites featuring controllable absorption peaks were obtained, demonstrating a transmittance of ∼81 % at 7 μm - the highest value ever reported for this composite system, which broadens the potential application space, particularly in fields requiring mid-infrared transparency such as gas detection, materials characterization, and biomedical imaging. This study not only elucidates specific strategies for enhancing the performance and microstructure of Y 2 O 3 MgO composites but also furnishes reliable methodologies and datasets to support the annealing processes of other material systems.
研究领域:
材料科学
·
光学材料
·
陶瓷
·
红外技术
·
固态化学
✓ 已验证
产品关联
DOI
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2020
·Vol. 22
·期 17
·9362-9367
·
IF 3.43
Weifeng Huang,Yingcai Zhu,Yong Liu,Lijuan Liu,Changchun Yang,Wei Xu
The quaternary chalcogenides consisting of earth-abundant elements such as Cu2ZnSnSe4 (CZTSe) have promising electrical and optical properties prompting enormous technological interest. Understanding different types of defects including Cu/Zn ordering is believed to be the key point to tackle technological challenges such as a large open circuit voltage deficit in CZTSe. The Te doped Cu2.2Zn0.8SnSe4−xTex (x = 0.01–0.04) were investigated using X-ray absorption fine structure spectroscopy at the Cu, Zn, and Se K-edges as well as at the Te L3-edge. Cu at the zinc site with anti-site defects and oxygen interstitials are identified. The detailed electronic structure upon Te doping is studied, providing insights into the rich defect chemistry present in this compound.
研究领域:
材料科学
·
凝聚态物理
·
无机化学
·
半导体材料
·
光电功能材料
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2013
·
IF 3.777
Mian Huang,Wei Xu,Yang Shen,Yuan-Hua Lin,Ce-Wen Nan
Ge-doped Li 7 La 3 Zr 2 O 12 (LLZ) is prepared via the conventional solid-state reaction. Our results showed that doping Ge of less than 1 wt% could stabilize the cubic phase of garnet-type LLZ and also increase its ionic conductivity up to 8.28 × 10 −4 S/cm at room temperature . When the content of Ge dopant is higher, GeO 2 impurity phase would appear and there coexists cubic and tetragonal mixed structures, lowering the conductivity. By combining X-ray absorption near-edge spectroscopy and full multiple-scattering theory, we find that Ge more likely enters into the Li and La crystallographic sites instead of the Zr site, which provides understanding of the micro-structural modulation by Ge dopants and the subsequent enhancement in the ionic conductivity.
研究领域:
材料科学
·
固体化学
·
光谱学
✓ 已验证
产品关联
DOI
高影响因子
DIAMOND AND RELATED MATERIALS
·
2025
·
IF 5.1
Long Wen,Jiangtao Huang,Jiaoning Tang,Peigang Han,Zongyan Zhang,Junrong Zeng,Jingwen Nan,Jinghong Yu,Chi Fang,Zihao Cheng,Jiaming Liang,Yang He,Liyu Lin,Bin He
The electrocatalytic nitrate (NO 3 − ) reduction to ammonia (NH 3 ) offers a solution for simultaneous environmental remediation and sustainable ammonia production. However, the rational design of nanocrystalline diamond (NCD) film electrodes balancing high activity and long-term stability remains a critical challenge. Herein, the defect chemistry and surface architecture of NCD films were tailored by adjusting the H 2 /Ar gas ratio in a mixed atmosphere of N 2 , CH 4 , Ar, and H 2 using hot-filament chemical vapor deposition (HFCVD). A series of NCD films with sp 3 /sp 2 ratios of 0.71, 1.14, 1.83, 3.12, and 6.14 were prepared by varying the H 2 /Ar gas ratio, corresponding to electrical conductivities of 18, 8.62, 7.94, 6.1, and 4.18 S/m, respectively. The sp 2 carbon phase serves as the primary active site for nitrate adsorption and electron transfer via its conjugated π-bond network. In addition, the sp 3 carbon phase provides structural stability through its robust tetrahedral framework. The electrode with the sp 3 /sp 2 ratio of 0.71 (H0) achieved the highest faradaic efficiency (FE) of 75.0 % for ammonia synthesis at −1.5 V (vs. RHE), whereas the electrode with the sp 3 /sp 2 ratio of 1.14 (H5) exhibited a slightly lower FE of 65.2 % but superior long-term stability, maintaining a steady faradaic efficiency over 50 h of operation. The optimal sp 3 /sp 2 ratio window (0.7–1.1) balances electron transport efficiency (sp 2 -dominated) and structural durability (sp 3 -dominated), revealing a synergistic interplay between defect-mediated conductivity and chemical robustness. Investigation of the mechanism reveals that optimal H 2 /Ar ratios selectively etch sp 2 impurities while preserving conductive pathways, creating a synergistic interplay between defect-mediated electron transport and chemically robust sp 3 frameworks. This study establishes a scalable strategy for engineering high-performance diamond electrocatalysts, bridging the gap between activity and durability in environmental electrochemistry.
研究领域:
材料科学
·
环境电化学
·
催化
·
纳米技术
·
表面科学
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2024
·
IF 13
Jiawei Li,Yating Peng,Peng Wang,Congyu Wang,Jun Zhang,Tengfei Xiang,Shengxun Yao,Dun Zhang
Triboelectric Nanogenerator (TENG) has proven highly effective in converting mechanical energy into electrical energy. Previous research on manipulating microstructure for performance enhancement primarily focused on the surface of TENGs. In this study, an innovative bottom–up strategic design to control the internal nano-architecture for the enhanced output of TENG is proposed. This multiscale structural design strategy consists of defect chemistry (angstrom-scale), surface modification (nano-scale), and spatial regulation of nanoparticles (meso-scale), which helps explore the optimal utilization of TENG's internal structure. After fine-tuning the nano-architecture, the output voltage is significantly increased. This optimized TENG serves as a robust platform for developing self-powered systems, including self-powered electrochemical chlorination systems for sterilization. Additionally, through the utilization of multiscale simulations (density functional theory, all-atom molecular dynamics, and dissipative particle dynamics), the underlying mechanisms governing how the optimized nanoparticle–polymer interface and spatial arrangement of nanoparticles influence the storage and transfer of charges are comprehensively elucidated. This study not only demonstrates the effectiveness of manipulating internal nano-architecture to enhance TENG performance for practical applications but also provides invaluable insights into structural engineering for TENG advancement.
研究领域:
材料科学
·
纳米技术
·
能量转换
·
电化学
·
模拟与建模
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of the American Chemical Society
·
2025
·
IF 15.6
Pei Liu,Mengmeng Zheng,Yue Wang,Xiang-Yu Kong,Yingjie Zhao,Mengru Zhang,Qun Xu,Lei Jiang,Liping Wen
The process of photosynthesis in green plants and energy conversion in certain archaea are inseparable from photoregulated ion pumping. Two-dimensional (2D) nanofluidic membranes, emerging as competitive candidates for constructing ion pumps, present intriguing prospects for harvesting light energy. However, the inevitable presence of defects during the synthesis of 2D materials underscores the critical need to understand their impact on ion transport dynamics within nanofluidic systems. Here, we present a chemically engineered asymmetric nanofluidic membrane (ANM) by intercalating molybdenum trioxide (MoO3) with controlled oxygen vacancies into graphene oxide laminates, systematically investigating the defect chemistry-governed photo-activated ion transport. Upon photoexcitation, MoO3 nanosheets exhibit tunable surface plasmon resonance (SPR) through photochemical H+ intercalation, leading to an augmentation of oxygen vacancies and an elevated concentration of free electrons. These vacancies enrich MoO3 with excess localized surface electrons, enabling tunable SPR that creates negative charge centers and significantly enhances space charge through defect-induced polarization. Density functional theory (DFT) calculations reveal the atomic-level mechanism of vacancy-enhanced cation transport, showing a notable 188% increase in the adsorption energy of K+ at MoO3 surfaces with two vacancy sites compared to one vacancy (−13.66 vs −4.74 eV). Under asymmetric photo irradiation, the system achieves a peak power density of approximately 439.2 W/cm2 in equilibrium ionic solutions, realizing a photonic-to-ionic energy conversion efficiency of 7.98 × 10–4% via synergistic effects of defects and plasmonics. Our research pioneers the elucidation of the regulation and underlying mechanisms of intrinsic defects on active ion transport within nanofluidic membranes, while fostering a novel perspective on photon–electron–ion interplay within nanofluidic environments.
研究领域:
纳米流体学
·
能量转换
·
材料科学
·
物理化学
·
光子学
·
电化学
·
凝聚态物理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2025
·Vol. 60
·期 48
·25148-25163
·
IF 3.9
Zhang Zhenyan,Chai Huan,Yu Zhengqian,Li Jinsheng,Li Pengfei,Wu Lei,Li Zhanshuai,Qi Xiwei
TiO 2 -based materials are widely used in high-temperature capacitors and aerospace electronics but face challenges such as high dielectric loss and limited thermal stability in conventional single-component systems. To address these issues, we propose a novel strategy integrating high-entropy doping design and oxygen vacancy engineering. In 2 O 3 -doped (GeMnTiSnMo)O 2 high-entropy ceramics (GMTSMO- x In, x = 0.1–1) were synthesized via solid-state reaction. Experimental results reveal that In 3+ doping generates high-density oxygen vacancies (V o ·· ) through charge compensation, forming [Ti 3+ - V o ·· -Ti 3+ ] and [Mn 3+ - V o ·· -Mn 3+ ] defect-dipole clusters. These clusters enhance electron localization and suppress carrier migration, reducing dielectric loss by threefold. Simultaneously, oxygen vacancy enrichment strengthens interfacial polarization, increasing the dielectric constant by fourfold. The optimal GMTSMO-0.5In exhibits a relative permittivity ( ε r ) of 4.0 × 10 6 and a low loss tangent of 15 at 650 ℃/100 Hz, outperforming traditional TiO 2 -based materials and existing high-entropy oxides. All compositions demonstrate excellent temperature stability (25–400 ℃) and frequency-independent behavior above 10 4 Hz. This work provides a high-entropy-driven approach for dynamic defect engineering, paving the way for advanced dielectric materials in extreme-condition energy storage systems.
研究领域:
材料科学
·
陶瓷与介电材料
·
电子材料
·
储能技术
·
缺陷化学
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2023
·Vol. 33
·期 33
·2302199
·
IF 19
Zhao-Yang Yin,Yang Chen,Yang-Yang Zhang,Yu Yuan,Qian Yang,Ya-Nan Zhong,Xu Gao,Jing Xiao,Zhao-Kui Wang,Jian-Long Xu,Sui-Dong Wang
Minimizing reverse bias dark current density ( J dark ) while retaining high external quantum efficiency is crucial for promising applications of perovskite photodiodes, and it remains challenging to elucidate the ultimate origin of J dark . It is demonstrated in this study that the surface defects induced by iodine vacancies are the main cause of J dark in perovskite photodiodes. In a targeted way, the surface defects are thoroughly passivated through a simple treatment with butylamine hydroiodide to form ultrathin 2D perovskite on its 3D bulk. In the passivated perovskite photodiodes, J dark as low as 3.78 × 10 -10 A cm -2 at -0.1 V is achieved, and the photoresponse is also enhanced, especially at low light intensities. A combination of the two improvements realizes high specific detectivity up to 1.46 × 10 12 Jones in the devices. It is clarified that the trap states induced by the surface defects can not only raise the generation-recombination current density associated with the Shockley–Read–Hall mechanisms in the dark (increasing J dark ), but also provide additional carrier recombination paths under light illumination (decreasing photocurrent). The critical role of surface defects on J dark of perovskite photodiodes suggests that making trap-free perovskite thin films, for example, by fine preparation and/or surface engineering, is a top priority for high-performance perovskite photodiodes.
研究领域:
光电子学
·
半导体器件物理
·
材料科学
·
表面工程
·
缺陷化学
·
光电探测器
✓ 已验证
DOI
高影响因子
ADVANCED MATERIALS
·
2025
·
IF 26.8
Shengbin Xu,Yao Xiao,Puxian Xiong,Pan Zheng,Sheng Wu,Xuesong Wang,Yumin Yin,Haiqiang Fang,Chengan Wang,Yuexi Lu,Enhai Song,Jiulin Gan
Mechanoluminescence (ML), the emission of light under mechanical stimuli, shows great potential in passive sensing, wearable devices, and biomedical diagnostics. However, the practical application of ML materials is hindered by low intensity and poor self-recoverable performance. Herein, a Mn 4+ →Mn 2+ self-reduction strategy is presented to significantly enhance the self-recoverable ML performance of CaZnOS by inducing lattice defects and promoting distortion in its noncentrosymmetric hexagonal structure. This approach enhances the internal piezoelectric response and increases the maximum ML intensity up to 4 times. X-ray absorption near-edge structure, extended X-ray absorption fine structure, electron paramagnetic resonance, piezoresponse force microscopy, and density functional theory calculations reveal that the composite defects involving V O · · ${\mathrm{V}}_{\mathrm{O}}^{\cdot \cdot}$ and V Zn ′ ′ ${\mathrm{V}}_{{\mathrm{Zn}}}^{{\mathrm{^{\prime\prime}}}}$ are the key to the significant enhancement of ML. Furthermore, this strategy is successfully extended to rare-earth ions codoped systems, achieving a general enhancement of near-infrared ML emission. Based on these findings, a multilayer orthodontic sensor is developed, capable of real-time occlusal mapping and bite-force monitoring. The device exhibits sensitive response across 0–12 N and achieves 96.89% accuracy in occlusal localization through neuromorphic image recognition. This work offers a generalizable route toward ML performance optimization and paves the way for the development of advanced intelligent sensing technologies.
研究领域:
材料科学
·
力致发光
·
压电材料
·
缺陷化学
·
传感器与传感技术
·
智能材料
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）