CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Yan Ziyang,Wu Angxuan,Wang Xilin,Huang Rongxia,Yan Nianping,Jia Zhidong,Wang Liming
In this paper, ZnO was used as a sintering aid as well as reactant in the reactive flash sintering (RFS) of zinc-containing ceramic materials at room temperature (25 °C). The RFS of ZnO-based ceramics, both ZnAl 2 O 4 and Zn 2 TiO 4 , were achieved with the application of a high electric field. Contrary to previous reports, the RFS of ZnAl 2 O 4 was divided into two stages according to temperature changes, and the effect of the reaction exotherm on the RFS was presented for the first time in this paper. In addition, the RFS produced a larger grain size of ZnAl 2 O 4 than conventional sintering did.
研究领域:
材料科学
·
陶瓷工程
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2018
·
IF 3.057
Haibin Sun,Xue Guo,Jiao Li,Guochang Li,Zanzhong Yang,Hao Ding,Weilu Yan,Shuai Qi,Peng Wang,Youjie Song
In order to clarify the effect of grain size on the electrical performance of BaZr 0.1 Ce 0.7 Y 0.1 Yb 0.1 O 3-δ (BZCYYb) solid electrolytes with addition of NiO, microcrystalline (~1.5 µm) and ultrafine-grained (~280 nm) BZCYYb electrolytes (with 1 wt% NiO) were fabricated by the conventional and two-step sintering method, respectively. The results show that compared with microcrystalline electrolytes, the ultrafine-grained electrolytes have similar grain-interior conductivities, but much lower grain-boundary conductivities, illustrating that the grain boundary is not conducive for ionic transport. As a result, the electrical conductivity of microcrystalline electrolytes (1.9 × 10 −2 S cm −1 at 600 °C in wet air) is higher than that of ultrafine-grained electrolytes (1.1 × 10 −2 S cm −1 at 600 °C in wet air). In addition, the OCV (open-circuit voltage) values of electrolyte-supported single cells show that the undesired electronic conduction exists in the electrolytes due to the BaY 2 NiO 5 impurity formed by the reaction of NiO and BZCYYb. The ultrafine-grained electrolytes show lower OCV values than that of microcrystalline ones, due to the prolonged electronic transport paths. Therefore, large-grained or grain boundary-free microstructure are necessary for improving the electrical performance of BZCYYb electrolytes.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2018
·
IF 3.057
Q.B. Chen,B. Meng,M.Y. Zhao,H. Xie,L.F. Bian,X. Yang
In order to investigate the grain size effect on the electrical conductivity of the submicron samarium-heavily-doped ceria , the Ce 0.8 Sm 0.2 O 1.9 (SDC20) ceramics with grain sizes from 128 nm to 533 nm were prepared by sintering at 1000–1300 °C in the air atmosphere. The crystalline structure, micro-morphology, density and electrical conductivity of the SDC20 ceramics were measured and characterized by XRD , SEM, TEM, Archimedes method and electrochemical impedance spectrum, respectively. All the sintered samples show the single SDC phase, low porosity and clean grain boundary without any impurities. The grain sizes of SDC ceramics grow continuously with the rising sintering temperature , and the relative densities increase as the sintering temperature rises from 1000 °C to 1200 °C and then decrease with the temperature from 1200 °C to 1300 °C. The specific grain boundary conductivity of SDC keeps decreasing while the grain and apparent grain boundary conductivities increase during the whole grain size range of 128–533 nm.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2017
·
IF 2.299
Misganaw Alemu Zeleke,Dong-Hau Kuo,Osman Ahmed Zelekew,Albert Daniel Saragih
Ge-substituted Cu 2 Sn(S,Se) 3 bulks with Cu 2 (Sn 1- x Ge x )(S,Se) 3 formula at x = 0, 0.25, 0.50, 0.75, and 1.0 were synthesized by reactive liquid phase sintering , where the heating process was held at 200 °C for 20 min before reaching the sintering temperature of 600 °C for 30 min. In the presence of volatile Sb 2 S 3 sintering aid , the effects on densification , grain boundary, crystalline size, and electrical properties of Ge-substitution were investigated. Cu 2 (Sn 1- x Ge x )(S,Se) 3 showed p-type behavior for all x values. It was found that the mobility was increased sharply and carrier concentration was decreased rapidly as the x -value was increased. The electrical conductivities were found to be 14.0, 22.7, 36.8, 126, and 153 S/cm at x = 0, 0.25, 0.50, 0.75, and 1.0, respectively. X-ray diffraction (XRD) peaks were shifted to the higher angle and band gaps increased upon successive increasing of the Ge/[Ge+Sn] fraction being 1.19, 1.21, 1.22, 1.24, and 1.26 eV at x = 0, 0.25, 0.50, 0.75, and 1.0, respectively. The studies of Ge-x-CTSSe bulks were based on Ge Sn defects and supported by the data of morphological, structural, electrical, and optical properties .
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
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2024
·
IF 5.8
Yixin Guo,Sijia Huo,Qingyi Kong,Lei Chen,Yujin Wang,Xinghong Zhang,Yu Zhou
Monolithic ZrB 2 , ZrB 2 -SiC, ZrB 2 -TiC and ZrB 2 -SiC-TiC were fabricated by hot pressing. Contour maps depicting grain size and mechanical properties were generated on the ZrB 2 -SiC-TiC ternary diagram through experimental data and software fitting. These visual representations effectively establish the relationships between chemical composition and material properties, despite the similar high hardness of three main compounds. Notably, the average grain size of ZrB 2 -SiC-TiC is significantly reduced by an order of magnitude compared to monolithic ZrB 2 . Both strength and hardness exhibit a strong correlation with grain size, while the elastic modulus demonstrates insensitivity to microstructure changes. The evolution of toughness proves to be complex.
研究领域:
材料科学
·
陶瓷工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Wei Ding,Pengjian Lu,Qingfang Xu,Chitengfei Zhang,Rong Tu,Song Zhang
In the integrated circuit industry, heat is transferred through the contact between wafers and the chemical vapor deposited (CVD) 3C–SiC wafer susceptor . Understanding the out-plane thermal conductivity of CVD 3C–SiC is crucial in this context. The influence of grain size and grain boundary characteristics on out-plane thermal conductivity for <111>-oriented CVD 3C–SiC was discussed in this study. The out-plane thermal conductivity sharply decreases from 146.4 W/m⸱K to 122.3 W/m⸱K when the grain size approaches 11.04 μm. This paper suggests that the significant accumulation of dislocations at high-angle grain boundaries is the primary cause of this phenomenon. The substantial lattice strain impedes phonon transfer between grain boundaries, reducing overall phonon mobility. These findings suggest that manipulating the grain boundary angle is an effective means to fine-tune heat transfer in <111>-oriented CVD 3C–SiC.
研究领域:
材料科学
·
热物理学
✓ 已验证
产品关联
DOI
高影响因子
ACS Omega
·
2024
·
IF 3.7
Xiaoyan Gan,Kegui Li,Longtao Du,Ruoqi Wang,Yuge Chang,Liling Guo,Hanxing Liu
This study explores the optimization of (TMA)2MA4Pb5I16 perovskite films by regulating the film quality through the addition of MACl and MAAc additives. We found that adding MACl resulted in a film of larger grains with a power conversion efficiency (PCE) of 5.34%, while excessive MACl led to the formation of low-dimensional phases. Adding 7.5% MAAc improved the film quality with a PCE of 5.64%, although excessive MAAc induces pores and smaller grains. To address these issues, we proposed the combined use of MACl and MAAc additives, resulting in films with a larger grain size, smoother surface, and denser structure. Remarkably, the addition of MAAc + MACl achieved a champion PCE of 8.86% with good reproducibility. Mechanism studies revealed that TMA and MAAc formed a stable complex with PbI2 in solution, disrupting nucleation laws and promoting the formation of nuclei, leading to denser films with smaller grains. Additionally, the MACl treatment effectively promoted grain growth, resulting in high-quality films. This study presents novel insights into dual additive usage and their role in film crystallization, offering valuable guidance for the preparation of high-performance perovskite films.
研究领域:
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS
·
2024
·
IF 1.3
Wenbin Jin,Nan Liu,Fang Cheng,Zongqing Ma,Yongchang Liu,Pingzhan Si,Hongliang Ge
We report the C substitution effects in MgB 2 bulks on the lattice parameters, FWHM, and critical current density ( J c ) as a function of doping level. It is shown that using carbon-coated boron powder can effectively control the grain growth of MgB 2 during the whole sintering process. Accompanied by the rapid cooling process, the final average grain size can be restrained within merely 50 nm, and the J c value of the sample can be significantly improved at high field. On top of that, adding Cu is also considered a key factor in improving the current carrying property of the graphene-doped sample throughout the whole field, which can be attributed to the formation of the MgCu 2 alloy phase.
研究领域:
材料科学
·
超导体研究
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2019
·
IF 1.911
Junqiang Zhang,Shu Zhang,Mei Zhong,Zhi Wang,Guoyu Qian,Junhao Liu,Xuzhong Gong
CaO needs to show high activity to be used as Ca-sorbent and slagging agent. Hydration activity is an important characteristic to evaluate the activity of CaO. In this study, carbide slag from polyvinyl chloride (PVC) industry was utilized as precursor for preparing high activity CaO. The roles of crystallite grain, average pore diameter (APD) and volume fraction of pore < 200 nm in diameter (VF200) in hydration activity of CaO from carbide slag (CS-CaO) were respectively investigated. The hydrolysis kinetics model of CaO shows a three-dimensional spherically symmetric diffusion model (D4), which suggests that hydration activity was mainly associated with APD and VF200 of CS-CaO with limited correlation to the crystal size. Specifically, the hydration activity of CS-CaO is increased with increasing VF200, while decreased with increasing APD. Under the invariable calcination temperature, the core–shell structure formed by the addition of graphite or CaCO 3 to CS effectively inhibits the sintering of CS-CaO and improves VF200. Consequently, the hydration activity of CS-CaO increased from 22.79 °C·min −1 to 27.19 °C·min −1 and to 29.27 °C·min −1 , with addition of 5% graphite or 5% CaCO 3 into carbide slag, respectively.
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
Processes
·
2022
·Vol. 10
·期 2
·420
·
IF 3.352
Wenfeng Zhang,Tongrui Hu,Tao Chen,Xiaowei Yang,Yunfeng Zhu,Tainian Yang,Liquan Li
In this work, Al-1Zn-0.1In-0.1Sn-0.5Mg-xMn (x = 0, 0.1, 0.2, 0.3) alloys are prepared and used as the anode of an Al-air battery (AAB). We use scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDS) and optical microscopy (OM) to analyze the microstructures of the alloys. The hydrogen evolution rate, electrochemical performance (including polarization curves), electrochemical impedance spectroscopy (EIS), and battery performance of the samples are examined in the 4 M NaOH electrolyte. The experimental data display that the average grain size is significantly refined after adding manganese into the Al-1Zn-0.1In-0.1Sn-0.5Mg alloy, with a decrease in grain size from over 100 μm to about 10 μm. The improved activity of the aluminum anode in the AAB can be attributed to the introduction of manganese. The Al-1Zn-0.1In-0.1Sn-0.5Mg-0.1Mn alloy possesses the optimal overall performance with a lower self-corrosion rate (0.128 mL∙cm−2∙min−1), the highest working potential (1.630 V) and energy density (2415 mWh·g−1), a higher capacity (1481 mAh·g−1) and anodic utilization (49.75%).Keywords:aluminum alloy;aluminum-air battery;self-corrosion;grain size;electrochemical performance
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS SCIENCE FORUM
·
2015
·
IF 0
Gang Chen,Chun Wei Gong,Chun Lin Fu,Xiao Dong Peng,Wei Cai,Rong Li Gao,Xiao Ling Deng
(Sr1-xBax) 2(Nb0.9Ta0.1) 2O7 (SBNT) ceramics were prepared by solid state reaction. The crystal structure of SBNT ceramics, surface morphology and dielectric properties were studied using XRD, SEM and LCR instrument analyzer, respectively. The results show that the grain size decreases with increasing Ba concentration, and all samples show single phase, no second phase can been observed. Addition of Ba ion can improve the dielectric properties of SBN ceramics. The dielectric constant increases first, then decreases; the maximum value (εr=97) can be obtained at x=0.1, the dielectric constant changes slightly with increasing wide frequency.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Nan Xin,Yifei Li,Guihua Tang,Tian Lan,Jimin Xu,Xin Zhao,Min Zhang,Yinan Nie,Hao Shen
Thermoelectric materials have great potential in the energy recovery and environmental protection, and thermoelectric films can also effectively achieve heat dissipation of the chip through thermoelectric refrigeration. WS 2 films show good thermoelectric performance in prediction, but the figure of merit ( ZT ) of the synthesized WS 2 films still needs improvement. In this work, Cu was doped into WS 2 films by magnetron sputtering combined with chemical vapor deposition and sulfurization annealing. Cu doping narrowed the band gap and increased the hole concentration from 5.6 × 10 19 cm −3 to 2.2 × 10 21 cm −3 , greatly improved the electrical properties of WS 2 film. At 300 K, the electrical conductivity and power factor of Cu-doped films increased by 1086 % and 575 % compared to pristine WS 2 , respectively. In addition, Cu doping reduced the grain size and introduced more grain boundaries, which decreased the in-plane thermal conductivity to as low as 0.22 W m −1 K −1 at 300 K. The coupling of the electrical and thermal properties optimization greatly improved ZT . The ZT value of Cu 5.5 -WS 2 films is as high as 0.181 at 425 K. This work provides a new idea for improving the thermoelectric performance of transition metal dichalcogenides (TMDCs) films.
研究领域:
材料科学
·
能源技术
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）