Materials
·
2019
·Vol. 12
·期 17
·2793
·
IF 2.972
Hongyu Dong,Xin Li,Yi Dong,Shaoqing Guo,Liangfu Zhao
In a conventional electrically conductive adhesive (ECA) preparation process, typical ECAs are made by adding an appropriate amount of electrically conductive fillers, such as silver, into a polymer matrix, such as epoxy resin, to form a uniformly dispersed mixture by mixing and stirring operations. However, during the preparation process, secondary pollution and mass loss are caused by the vigorous mixture process. At the same time, the stirring operation introduces many small and stable bubbles, which affect the electrical conductivity of the ECAs. In light of these problems with the conventional preparation of ECAs, we developed a novel ECA preparation method that employs a powder spraying process: silver flakes are sprayed into the epoxy resin with a certain mass fraction to form formulated pastes. The as-prepared ECAs exhibited excellent properties compared with those prepared by the conventional process. This proves that the powder spraying process is feasible and superior to the conventional process.Keywords:electrically conductive adhesives;silver flakes;electrical resistivity
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
PubMed
高影响因子
Entropy
·
2022
·Vol. 24
·期 5
·624
·
IF 2.738
Zhiwen Zhang,Xiaosen Li,Zhaoyang Chen,Yu Zhang,Hao Peng
The phase fraction measurement of gas-water-sand fluid in downhole is an important premise for safe and stable exploitation of natural gas hydrates, but the existing phase fraction measurement device for oil and natural gas exploitation can’t be directly applied to hydrate exploitation. In this work, the electrical resistivity properties of different gas-water-sand fluid were experimentally investigated using the multiphase flow loop and static solution experiments. The effect of gas phase fraction and gas bubbles distribution, sand fraction and sand particle size on the relative resistivity of the multiphase fluid were systematically studied. The measurement devices and operating parameters were also optimized. A novel combined resistivity method was developed, which demonstrated a good effect for the measurement of phase fractions of gas-water-sand fluid, and will have a good application potential in marine natural gas hydrates exploitation.Keywords:natural gas hydrates;sand production;multiphase fluid;phase fraction measurement;electrical resistivity;combined resistivity method
研究领域:
海洋工程
·
能源开发
✓ 已验证
产品关联
DOI
PubMed
高影响因子
WATER RESOURCES RESEARCH
·
2022
·Vol. 58
·期 12
·e2022WR033233
·
IF 6.159
Siyuan Qiang,Xiaoqing Shi,André Revil,Xueyuan Kang,Yuanyuan Liu,Jichun Wu
Characterizing residual non-aqueous phase liquids (NAPLs) in porous media is essential for designing contaminated site remediation strategies. The direct current resistivity method is increasingly being used at sites contaminated by NAPLs, which uses the Archie's second law to connect NAPL saturation with the resistivity of porous media. A power-law relationship connecting the phase morphology measured by Euler characteristic with resistivity has also been observed at the pore-scale. Because these relationships are limited for porous media with specific wettability, previous research works have demonstrated deviations from Archie's second law in both the laboratory and field experiments. To evaluate the effects of residual NAPL morphology with different wettability on bulk resistivity, we developed two 2D-micromodels and measured their electrical resistivity and phase morphology during phase displacement under laboratory-controlled conditions. Furthermore, pore network simulations of a variety of conditions were performed in absence of surface conduction. Results show that NAPL distributed in dead ends of the pore space has limited influence on bulk resistivity since they do not control the current path and voltage distribution. The correlations between resistivity index and Euler characteristic are determined by NAPL ganglia size and pore throat width. A power-law relationship is found between the Archie's saturation exponent and the average size of the residual NAPL ganglia, indicating that this exponent can be interpreted as the rate of change of the pore water connectivity with saturation. These insights provide a physical framework connecting the morphology and wettability of the NAPL ganglia with the Archie's saturation exponent. Key Points Non-aqueous phase liquid (NAPL) trapped in dead ends of porous space has little effect on bulk resistivity Relationship between the bulk resistivity and Euler characteristic of partially saturated pore network is determined by NAPL wettability A power-law relationship is found between the Archie's saturation exponent and NAPL ganglia size Plain Language Summary Petrophysical relationships can relate the non-aqueous phase liquids (NAPLs) saturation with subsurface resistivity, which help us to characterize the underground contaminants. However, researchers often encountered deviations from widely adopted petrophysical relationships that link the electrical resistivity with NAPL saturation because they neglect or wrongly predict the effect of NAPL morphology on resistivity. In our study, we systematically explored the mechanism behind the impact of NAPL morphology on electrical resistivity by micromodel experiments and pore network simulation.
研究领域:
环境科学
·
地球物理
·
水文地质学
·
污染水文学
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED PHYSICS
·
2024
·Vol. 135
·期 16
·
IF 2.7
Zhao Dongpeng,Li Jun,Bai Han,Wu Huantong,Chen Xiping,Sun Guangai,Zhou Zhongxiang
Consistent c -axis orientation characteristics toward the direction of applied pressure of Y -type BaSrCo 2 Fe 11 AlO 22 (BSCFAO- θ ) were successfully prepared by the strategy of hot pressing. The samples’ magnetoelectric coupling performance was greatly enhanced by the strategy of hot pressing than that of the traditional solid reaction method. The magnetoelectric current of BSCFAO- θ ( θ = 0°) (12.06 μ A/m 2 ) was nearly 5 times higher than BSCFAO- SS (2.24 μ A/m 2 ). The magnetoelectric polarization of BSCFAO- θ ( θ = 0°) (32.82 μ C/m 2 ) was nearly 4 times higher than that of BSCFAO- SS (8.31 μ C/m 2 ). The magnetoelectric coupling coefficients of BSCFAO- θ ( θ = 0°) (1880 ps/m) were nearly 4 times higher than those of BSCFAO- SS (404 ps/m). The enhancement of magnetoelectric polarization of BSCFAO- θ ( θ = 0°) can be attributed to the uniform c -axis orientation, which reinforced magnetoelectric polarization compared with none orientation that eliminated the magnetoelectric polarization on grain boundaries. The magnetoelectric coupling performance of BSCFAO- θ presented a gradually decreasing trend with the angle changing from 0° to 90° for the changing of orientation. Compared with traditional solid reaction methods, the strategy of hot pressing inhibits grain growth and increases grain boundaries, thus facilitating the enhancement of grain boundaries’ resistivity, and the electrical resistivity of BSCFAO- θ (3.08 × 10 10 Ω cm) was nearly 10 000 times higher than that of BSCFAO- SS (2.5 × 10 6 Ω cm), which also benefits the magnetoelectric polarization performance of BSCFAO- θ . Therefore, the hot-pressing strategy can contribute to the forming of oriented ceramics and enhance the grain boundaries’ resistivity to improve magnetoelectric coupling performance.
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2018
·Vol. 6
·期 46
·23388-23395
·
IF 9.931
Qihao Sun,Yadong Xu,Hongjian Zhang,Bao Xiao,Xin Liu,Jiangpeng Dong,Yuanbo Cheng,Binbin Zhang,Wanqi Jie,Mercouri G. Kanatzidis
The halide perovskitoid compound Cs3Bi2I9 (CBI) has attracted considerable interest as a semiconductor because of its outstanding stability and reduced toxicity compared with lead-based halide perovskites. Here, we report the growth of nuclear radiation detection grade CBI bulk crystals (Φ 15 × 60 mm3) with a high resistivity of over 1010 Ω cm using a modified vertical Bridgman method. Because of their layered crystal structures we investigated the anisotropy in the optical and electrical properties using different crystal orientations. The CBI(001) sample exhibits a resistivity of ∼1012 Ω cm compared to ∼1010 Ω cm for the CBI(100) sample. This is due to the anisotropic mobility in the two crystallographic directions. Using 425 nm LED (∼200 mW cm−2) illumination CBI(001) possesses a superior optical response with a switching ratio of over 40, which is critically higher than that of CBI(100) (<2). Detectors of 2 mm thickness show a capability of detecting 241Am@5.49 MeV α particles, with good peak discrimination. A full width at half maximum (FWHM) of 32% was obtained under a bias of 560 V. Simultaneously, the electron mobility and mobility lifetime (μτ) were calculated to be 6.10 cm2 V−1 s−1 and 2.03 × 10−5 cm V−1, respectively. First-principles density functional theory calculations confirm the crystallographic anisotropy of the carrier effective masses. In addition, a significant X-ray sensitivity of 111.9 μC Gy−1 cm−2 for a CBI detector was observed, under 80 kVp X-rays at an electrical field of 450 V cm−1.
研究领域:
材料科学
·
物理学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Wei Zheng,Lingyan Xu,Yingming Wang,Chongqi Liu,Lu Liang,Zhentao Qin,Lixiang Lian,Yanyan Lei,Qinzeng Hu,Wanqi Jie
Organic semiconductor single crystals with tissue-equivalent properties present promising advantages for detecting ionizing radiation, particularly X-rays. However, few organic semiconductor materials can exhibit excellent radiation detection performance. In this study, we focus on 9,10-bis(phenylethynyl)anthracene (BPEA) single crystals with two different crystalline phases (α-BPEA and β-BPEA). A slow solution evaporation method is employed to grow centimeter-sized α-BPEA and β-BPEA crystals with high quality. The sandwich-type α-BPEA detector demonstrates exceptional ionizing radiation detection capabilities, with resistivity of 2.72 × 10 12 Ω cm and hole mobility of 2.93 cm 2 V −1 s −1 . The α-BPEA detector also achieves rapid detection of 5.49 MeV α-particles with detection time of 7 ms. The energy resolution and hole mobility-lifetime product are calculated to be 29.93 % and 2.51 × 10 −5 cm 2 V −1 , respectively, marking the best α-particle energy spectrum performance among current organic semiconductor detectors. The α-BPEA detector exhibits X-ray detection sensitivity as high as 451.37 μC Gy air −1 cm −2 and detection of limit as low as 26.28 nGy air s −1 . The α-BPEA detector also demonstrates good operational stability and outstanding imaging capabilities, achieving a spatial resolution of 1.6 lp mm −1 . The BPEA single crystals suggest significant potential for direct ionizing radiation detection and broader optoelectronic applications.
研究领域:
材料科学
·
辐射探测
·
有机半导体
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2024
·
IF 3.2
Yunfei Wang,Hao Sun,Yafei Liu,Lili Zhi,Aimin Chang,Bo Zhang
Perovskite lanthanum chromate (LaCrO 3 ) has been widely investigated for applications as functional material, its properties can be finely tuned through doping. This study explores the effect of Al 3+ doping on the structure and electrical properties of La 0.9 Sr 0.1 Cr 1- x Al x O 3 ceramics. Our findings reveal that Al 3+ doping significantly influences the consistency of grain size and electrical transport properties of these ceramics. As x increases, the grain size decreases and obtains its minimum at x = 0.5. Compared to the undoped La 0.9 Sr 0.1 CrO 3 , Al 3+ doping significantly reduces the resistivity. For x = 0.3, the resistivity obtains its minimum 142.60 Ω cm at −75 °C, while the B -value is reduced to 405 K. These results demonstrate the potential of Al 3+ doping in enhancing the thermal sensing properties of LaCrO 3 ceramics and understanding of semiconductor behavior for electron device applications.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
VACUUM
·
2023
·
IF 4
Zhe Huang,Siyuan Wu,Baishan Chen,Siwei Tang,Yunzhu Ma,Wensheng Liu
Defects deteriorate the optical and electronic properties of the cadmium zinc telluride (CZT) single crystal . However, the growth of defects, such as vacancies and precipitation, could not be avoided in the industrial-grade preparation of CZT single crystal. Therefore, it is crucial to explore ways to eliminate defects after growth. This paper employs one-step heat treatment with the CdTe compound as an annealing atmosphere source. After annealing, some large-size Te inclusions are eliminated in CZT crystal, but nano Te precipitates still exist. At the same time, the crystal surface becomes rougher, caused by the thermal migration of Te droplets, dislocation proliferation, and aggregation. Increasing annealing time, dislocations migrate, decompose, and interact with each other to form dislocation walls, stacking faults or terminating at the surface, reducing dislocation etch pit density. In addition, a large number of ordered phases are still found in the crystal. Single annealing with CdTe significantly improved the crystal's optical and electrical properties. After 180 h annealing, the infrared (IR) transmittance of the as-grown wafer increased from 40% to 65%, and resistivity increased from 2.2 × 10 9 Ω cm to 1.7 × 10 11 Ω cm. Compared to reducing the Te precipitation phase, these increasements were mainly dominated by replacing point defects , like Cd vacancies.
研究领域:
材料科学
·
半导体物理
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2023
·Vol. 34
·期 6
·1-9
·
IF 2.8
Chen Wei,Sun Hui,Jin Yingrong,Yang Hualin,He Yi,Zhu Xinghua
Cs 3 Bi 2 I 6 Br 3 perovskite is one of the bismuth iodide family compounds. Because it contains no toxic lead, and has high stability in air and humidity, endowing a potential application prospects in photoelectric and radiation detectors. Herein, the Cs 3 Bi 2 I 6 Br 3 single crystal (Φ13 × 65 mm 3 ) with a (001) preferred direction was grown by using the melt method with solvent-synthesized polycrystalline particles, and the thin single wafer with a thickness up to 0.95 mm was obtained. The as-grown single crystal possesses high infrared transmittance of up to 70% in the range from 400 to 4000 cm −1 and an optical band gap of about 2.03 eV estimated from the visible absorption curve. A highly intrinsic resistivity 2.3 × 10 10 Ω·cm and a dielectric constant about 10 were obtained from the electrical performance parameter measurements. The X-ray sensitivity of the X-ray detector is 55.62 µC/Gy air /cm 2 (incident dose rate 0.24 mGy/s), as well as the signal-to-noise ratio, is up to 301. These results indicate Cs 3 Bi 2 I 6 Br 3 single crystals are a potential material for X-ray detection.
研究领域:
材料科学
·
光电检测
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Physics
·
2024
·
IF 10
Biao Zhang,Liming Quan,Zhihong Luo,Qiantong Li,Jianming Deng,Shuhang Yu,Wangxin Li,Mingmei Lin,Feng Yan,Dawei Wang,Dongyan Yu,Changbai Long,Laijun Liu
CaBi 2 Nb 2 O 9 (CBNO) ceramics exhibit significant potential in the development of piezoelectric sensors suitable for extreme environments such as aerospace, metallurgy, and nuclear power plants. While previous studies have enhanced the piezoelectric response of CBNO ceramics, their insulating properties at high temperatures still require improvement. In this work, co-substitution of (Li 0.5 Bi 0.5 ) at A site and Mn at B site was designed to improve the electrical properties of CBNO ceramics. Defect dipoles induced by the bound between Mn and oxygen vacancies restrict the movement of oxygen vacancies at high temperatures. Meanwhile, co-substitution of Ca by (Li 0.5 Bi 0.5 ) reduces both the sintering temperature and volatilization of Bi 2 O 3 during the sintering process. This modification results in an ultra-high T C of 928 °C and an exceptional resistivity of 2.85 MΩ cm at 600 °C for Ca 0.96 (Li 0.5 Bi 0.5 ) 0.04 Bi 2 Nb 1.98 Mn 0.02 O 9 ceramics. Furthermore, the ceramic exhibits excellent piezoelectric properties ( d 33 of 15.2 pC/N and k p of 6.9 %), ferroelectric properties ( P r of 9.42 μC/cm 2 ), and thermal stability (degeneration of d 33 only 6 % after annealing at 900 °C for 2 h). This work offers a practical strategy for simultaneously achieving both a high piezoelectric response and outstanding insulating properties in the CBNO system.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
Materials Research Express
·
2023
·Vol. 10
·期 4
·045201
·
IF 2.3
Yun Chuan Liu,Li Ying Zhang,Xiang Lei Yu,Wei Chao Li,Jun Peng Li,Guo You Gan
A high-temperature conductive silver slurry containing lead-free ZnO-B2O3-SiO2 glass for metallization of ceramic MgTiO3 substrate has been prepared. The ZnO-B2O3-SiO2 glass was obtained by high-temperature melting and cold extraction with a transition temperature (Tg) of 579 °C and thermal stability (∆T) of 105 °C as an inorganic bonding phase of high-temperature conductive silver paste. Then, silver paste with different glass powder content was sintered on ceramic MgTiO3 substrate between 730 °C and 930 °C in increments of 50 °C. Characterization of the prepared materials revealed that their resistivity increases with the increase in glass powder content and decreases with the increase in sintering temperature. Sintering temperature and glass content have significant effects on the resistivity and adhesion of the thick silver film. When the silver paste with a glass content of 1.1 wt% was sintered at 830 °C for 10 min, the resulting thick silver film had a low resistivity of 1.81 μΩ·cm (1.65 μΩ·cm for silver) and a good adhesive strength of 39.4 N mm−2. During the sintering process, the glass material melts and wets the silver powder, which promotes the sintering of the silver powder to form a dense network structure and improves the electrical conductivity of the silver film. In addition, the formation of ZnTiO3 by chemical reactions between the glass and the substrate was observed, which dramatically improved the bonding strength of the silver film. Therefore, lead-free silver paste containing ZnO-B2O3-SiO2 glass powder and MgTiO3 ceramics has broad development prospects in ceramic filters.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
Science China-Materials
·
2025
·
IF 7.4
Guo Ruiang,Li Shuaiqi,Zhang Jiawei,Tian Yi,Dong Weiguo,He Duanwei
Diamond is known as the ultimate semiconductor owing to its excellent physical properties. However, the high difficulty of n-type doping and the poor electrical performance of n-type diamonds remain major challenges for the application of diamond semiconductor materials. In this paper, a high-pressure thermal diffusion method for the n-type doping of diamond, which utilizes high pressure to reduce the volume difference between phosphorus atoms and carbon atoms, is reported for the first time. This method can achieve efficient doping and ionization of phosphorus atoms at the lattice sites of diamond. The prepared phosphorus-doped diamond exhibited the lowest resistivity (2 Ω cm) and highest electron concentration (2.27 × 10 18 cm −3 ) observed in any known phosphorus-doped diamond single crystal at room temperature (300 K). The high-pressure thermal diffusion method provides an effective approach for diamond n-type doping, which may play an important role in the design and preparation of future diamond-based semiconductor devices.
研究领域:
材料科学
·
半导体物理
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）