CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Yunzhu Ma,Haotian Liu,Chaozhong Wu,Wensheng Liu,Juan Wang,Shuwei Yao
The preparation of high-performance Al 2 O 3 -ZrO 2 fibers is a significant and challenging task. In this study, continuous Al 2 O 3 -ZrO 2 fibers were synthesized via the sol-gel method using aluminum powder and zirconium acetate as raw materials. It was observed that the amorphous state of Al 2 O 3 transformed into γ-Al 2 O 3 and then to α-Al 2 O 3 , while the amorphous ZrO 2 directly transformed into t-ZrO 2 . The formation temperatures of t-ZrO 2 and α-Al 2 O 3 were both approximately 1100 °C. The optimal sintering temperature during the single-step sintering process for Al 2 O 3 -ZrO 2 fibers was 1400 °C. Based on the experiment results, fully dense Al 2 O 3 -ZrO 2 fibers with fine grains were successfully synthesized via a two-step sintering process. The average sizes of Al 2 O 3 and ZrO 2 grains were 153 nm and 62 nm, respectively. The Weibull strength of the Al 2 O 3 -ZrO 2 fibers reached 2.2 GPa with a peak value of 2.6 GPa, which exhibited an increase of approximately 30% compared to that formed by the single-step sintering process. Furthermore, the nucleation, growth, and densification behaviors of Al 2 O 3 -ZrO 2 fibers during the two-step sintering process were discussed.
研究领域:
材料科学
·
陶瓷学
·
纤维科学
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DOI
高影响因子
CATALYSIS LETTERS
·
2023
·Vol. 154
·期 5
·2386-2395
·
IF 2.8
Xu Hui,Xing Feifei,Guo Yue,Wang Fei,Feng Junfeng,Li Hui,Jiang Xiaoxiang
To explore a green, cheap, and high-performance catalyst for lipid hydrotreatment into green diesel, the non-noble metal catalysts (Fe, Cu, Co, Ni, and Mo) with Al 2 O 3 carrier were prepared. Their catalytic performance in oleic acid hydrotreatment was compared, and the metal loading was studied. The characterizations (XRD, N 2 physical sorption, H 2 -TPR, and XPS) were utilized to elucidate the catalytic property. In oleic acid hydrotreatment, the catalytic activity of 5 monometallic catalysts was in the following order: Co > Mo > Ni > Fe > Cu, and the Co/Al 2 O 3 catalyst achieved 94.4% conversion and 91.8% alkane yield. Among 6 Co loadings (5, 10, 15, 20, 25, and 30 wt%), 25 wt% was optimal because it reached the balance of the surface area and the number of Co active sites. Moreover, the lipid hydrotreatment over Co/Al 2 O 3 catalyst occurred mainly via DCX/DCN route; meanwhile, the cracking reaction also happened. Graphical Abstract
研究领域:
能源化学
·
催化科学
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DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Kai Li,Ming Qiang,Jia Tong,Kaichen Qian,Yanna Tian,Bingheng Sun,Long Zhang,Wei Wu,Jintai Fan,Xiaomeng Yin
In this study, Al 2 O 3 -doped Y 2 O 3 -MgO nanocomposite ceramics were synthesized to inhibit abnormal grain growth. Y 2 O 3 -MgO nanopowders were synthesized using a sol-gel combustion approach. Two distinct Al 2 O 3 doping methods were employed: aluminum nitrate doping during the solution preparation stage and aluminum isopropoxide doping during the ball-milling stage of powder preparation processing. This study presents a comparative analysis of the effect of two doping methods on the performance and microstructure of ceramics. Doping during the solution preparation process can provide a more homogeneous distribution of Al 2 O 3 , which facilitated the formation of a minor Y 4 Al 2 O 9 phase. This tertiary phase effectively inhibited abnormal grain growth and improved mid-infrared transmittance. However, Al-O bonds cause a blue shift of transmission cut-off edge and an increase of emissivity, though the practical consequences for device performance require further investigation.
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2025
·
IF 9
Jia'nan Wang,Can Cheng,Jiaying Xu,Zhisong Liu,Haomiao Xu,Wenjun Huang,Zan Qu,Naiqiang Yan
Tetrafluoromethane (CF 4 ), a highly potent greenhouse gas characterized by the notable capacity to absorb infrared radiation, making its effective control essential for mitigating global warming. However, the activation of CF 4 faces challenges in the conventional approaches caused by its symmetric structure and strong C F bonds. In this work, we presented an approach to enhance the activation of C F bonds using an inductance-enhanced Ce/Al 2 O 3 catalyst within the designed plasma-catalytic reaction system featuring a step-discharge effect. The optimal CF 4 decomposition efficiency reached approximately 89.5 % at the power of 18 W, while maintaining above 88.6 % for 24 h. The impact of plasma conditions and flue gas parameters on CF 4 decomposition and energy efficiency was also investigated. Py-IR showed that the Ce/Al 2 O 3 catalyst provided more Lewis acid sites as the active centers for breaking C F bonds. In situ FTIR and in situ OES studies revealed that the intermediates generated from CF 4 decomposition can react with active oxygen to form C O bond under the plasma-catalytic effect, preventing the reformation of C F bonds. DFT calculations demonstrated that the Ce/Al 2 O 3 exhibited a lower energy barrier to dissociate CF 4 and a stronger adsorption for O 2 . This work established a novel pathway for the activation of C F bonds to achieve the efficient decomposition of CF 4 at low temperatures.
研究领域:
环境化学
·
等离子体催化
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材料科学
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温室气体减排
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表面化学
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产品关联
DOI
高影响因子
ACS Catalysis
·
2025
·
IF 13.1
Chuang Gao,Didi Li,Huihua Pan,Hansheng Wang,Yifeng Zhu,Yiying Tang,Minghui Zhu,Zixu Yang,Jing Xu
Controlling product selectivity in platinum-based catalysts during hydrocarbon reforming is a critical challenge, with the main difficulty being the suppression of side reactions like hydrogenolysis. In this work, we report a facile and scalable in situ strategy that significantly enhances the yield of aromatics by activating Pt/Al2O3 catalyst in a propane atmosphere. We demonstrate that this method results in selective deposition of a functional carbon overlayer onto excessively active metal–support interface sites, thereby suppressing the hydrogenolysis pathway, the primary source of low-carbon byproducts. As a result, the selectivity for aromatics nearly doubled, increasing from 17% for the conventionally hydrogen-reduced catalyst to 32%. This work not only transforms carbon deposition from a deactivation factor into a tool for precisely tuning active sites but also provides a powerful strategy for developing highly efficient reforming catalysts.
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产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2025
·
IF 5.4
Juan Zhang,Yu Wei,Zhiquan Wu,Hang Gao,Wenchao Gao,Libo Li,Yang Chen,Honghong Chang
To address the issue of water formation leading to the collapse of catalyst structure and diminished catalytic activity during the synthesis of indole via reaction of ethylene glycol and aniline, a series of hydrophobic Pt/Al 2 O 3 catalysts have been engineered through surface chemical modification. Herein, alkyltriethoxysilane and alkyl phosphonic acid were employed as modifiers to decorate the surface of Pt/Al 2 O 3 , preparing hydrophobic catalyst (Pt/Al 2 O 3 -R), and the quantity of these hydrophobic reagents were selectively regulated to ascertain the catalyst with optimal efficiency. In the course of this procedure, the catalyst Pt/Al 2 O 3 -0.03SiC 12 , which exhibited a water contact angle of 112° and an ethylene glycol contact angle of 62°, significantly enhanced the yield of indole to 72%. It has been established that variations in the alkyl chain length impact the hydrophobicity and wettability of ethylene glycol, collectively influencing the catalytic efficiency. X-ray photoelectron spectroscopy (XPS) and Fourier-transform infrared spectroscopy (FT-IR) confirmed successful integration of the chemical modifier onto the Al 2 O 3 surface via Si-O bonds. Furthermore, XRD, TEM, and BET results indicate that although the surface hydrophobic modification has a certain impact on the metal-active center, whereas the hydrophobic microenvironment is highly effective for the conversion of ethylene glycol to indole. DFT calculations further supported this finding, showing reduced water adsorption energy on the modified Pt/Al 2 O 3 surface. This study highlights the role of alkyl chains in modulating hydrophobicity and substrate wettability in the context of indole synthesis, offering insights into the design of catalysts for other dehydration reactions.
研究领域:
催化化学
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有机合成
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材料科学
·
表面科学
·
工业化学
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产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2023
·
IF 4.2
Lin Mei,Chao Feng,Yuzhong Wang,Qiang Yu,Wenjie Xin,Weifeng Chu,Yanan Wang,Xiangxue Zhu,Shenglin Liu,Hongxia Wang,Longya Xu
Synthesis of acetonitrile (ACN) by way of ethanol dehydroamination process was performed over copper-, zinc-, nickel-, and cobalt-based catalysts in a fixed-bed reactor, by which 20Co/Al2O3 was found to be the best one and ready for subsequent La, Ce, and Pr doping. Then, catalytic tests and a series of characterizations such as XRD, XRF, XPS, TEM, TG-DTA, IGA, NH3-TPD, and N2 adsorption–desorption were carried out. The results demonstrate that rare-earth-modified 20Co/Al2O3 catalysts have improved the catalytic performance for ethanol dehydroamination remarkably; the addition of La leads to better dispersion of cobalt species, the higher surface area of 20Co/Al2O3 catalyst, and fast adsorption for ACN, as well as better resistance to carbon deposition. In the meantime, the La-doped catalyst seems to prefer the route of acetaldehyde imine to ACN rather than to ethylamine, and consequently, a highly selective synthesis of ACN with excellent catalytic stability was obtained with the formation of ethylamine being suppressed..
研究领域:
催化化学
·
材料科学
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DOI
高影响因子
CERAMICS INTERNATIONAL
·
2013
·
IF 1.789
Mingye Ding,Chunhua Lu,Qiaoqiao Cui,Yaru Ni,Zhongzi Xu
Glasses within the B 2 O 3 –Al 2 O 3 –Na 2 O system were examined as potential replacements for PbO-based glass frits with low firing temperature (500–600 °C) for transparent dielectric layer of plasma display panel (PDP). The glasses were evaluated for glass transition ( T g ), softening temperature ( T f ), thermal coefficient of expansion ( α ) and dielectric constant ( ε ). The dielectric constant of these glasses was also compared with theoretical data calculated by Appen and Bresker's equation. T g of the glasses varied between 330 and 460 °C and T f was in the region of 350–500 °C. The thermal coefficient of expansion ranged from 7×10 −6 to 10×10 −6 K −1 . The dielectric constant of these glasses was 6–8 within the region of the theoretical value. The T g , T f , α , ε of the selected glass, which was used to prepare transparent dielectric layer in 20 μm thickness, were found to be 449 °C, 476 °C, 8.284×10 −6 /k, 6.84, respectively. All the results suggest that B 2 O 3 –Al 2 O 3 –Na 2 O glasses would be suitable as a potential candidate for Pb-free dielectric layer in PDPs.
研究领域:
材料科学
·
电子工程
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DOI
高影响因子
AICHE JOURNAL
·
2017
·Vol. 63
·期 11
·4911-4919
·
IF 2.836
Tengfang Wu,Gang Liu,Liang Zeng,Guodong Sun,Sai Chen,Rentao Mu,Sika Agbotse Gbonfoun,Zhi-Jian Zhao,Jinlong Gong
Supported VO x catalysts are promising nonoxidative propane dehydrogenation (PDH) materials for their commercially attractive activity and propylene selectivity. However, they frequently suffer from rapid deactivation caused by coke deposition. This article describes the promoting role of magnesium on the stability of VO x /Al 2 O 3 catalysts for PDH. A series of VO x /Al 2 O 3 and Mg-modified VO x /Al 2 O 3 catalysts were synthesized by an incipient wetness impregnation method. The catalysts were carefully characterized by Raman spectra, UV-Vis spectra, STEM, TGA and in situ DRIFTS. We showed that the stability of a 12V/Al 2 O 3 catalyst was significantly improved on addition of small amounts of MgO. Experimental evidences indicate that V 2 O 5 nanoparticles emerge in the 12V/Al 2 O 3 samples, and appropriate Mg addition helps dispersing the V 2 O 5 nanoparticles into 2D VO x species thus decreasing coke formation and improving stability in nonoxidative dehydrogenation of propane. © 2017 American Institute of Chemical Engineers AIChE J , 2017
研究领域:
催化化学
·
工业催化
·
材料化学
·
能源化工
·
多相催化
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DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
·
2022
·
IF 10.319
Wenqiang Hu,Wenbin Fu,Samik Jhulki,Liang Chen,Aashray Narla,Zhijian Sun,Fujia Wang,Alexandre Magasinski,Gleb Yushin
Poor heat/flame-resistance of polyolefin (e.g., polyethylene and polypropylene) separators and high flammability of organic electrolytes used in today's lithium-ion batteries (LIBs) may trigger rare yet potentially catastrophic safety issues. Here, we mitigate this challenge by developing a heat-resistant and flame-retardant porous composite membrane composed of polyetherimide (PEI) and Al 2 O 3 nanowires (NWs). The membranes are fabricated based on an industrially scalable non-solvent-induced phase separation process, which results in an intimately interconnected porous network of Al 2 O 3 NWs and PEI . The produced composite membranes exhibit excellent flexibility, thermal stability, and flame-retardancy. Importantly, the composite membranes exhibit minimal thermal shrinkage and superior tensile strength (16 MPa) at temperatures as high as 200 °C, significantly exceeding the performance of conventional polyolefin separators. Compared with commercial separators, their superior wettability and higher ionic conductivity (by up to 2.4 times) when filled with the same electrolyte, larger electrolyte uptake (∼190 wt.%), as well as improved cycle and rate performance demonstrated in LiNiMnCoO 2 (NCM)-based LIBs make them attractive choices for a variety of electrochemical energy storage devices.
研究领域:
材料科学
·
电化学
·
能源存储
·
高分子科学
·
纳米技术
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DOI
高影响因子
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
·
2020
·
IF 4.652
Jianlong Chai,Yabin Zhu,Zhiguang Wang,Tielong Shen,Yiwen Liu,Lijuan Niu,Shufen Li,Cunfeng Yao,Minghuan Cui,Chao Liu
Al 2 O 3 –ZrO 2 (3Y)–SiC ceramic composites were prepared by spark plasma sintering in vacuum under 40 MPa of uniaxial compression between 1300 °C and 1400 °C. The effect of nano-size SiC and sintering temperature on the microstructure and mechanical properties of ceramic composites were investigated. The results showed that SiC particles was uniformly distributed in the composite, mainly within the matrix grains. Sintering temperature and SiC particles caused the shape of alumina grains to be columnar. The flexural strength of 22.3 vol% Al 2 O 3 -57.7 vol% ZrO 2 -20 vol% SiC sintered at 1350 °C composites was 1081 MPa, fracture toughness was 15.18 MPa m 1/2 and hardness was 16.42 GPa. The addition of SiC particles leads to grain boundary strengthening, and the change of fracture mode and cracks deflection and bridging are considered to be the main reasons for the increase in material fracture toughness.
研究领域:
材料科学
·
陶瓷学
·
复合材料
·
固态物理
·
结构材料
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DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2021
·Vol. 104
·期 7
·3260-3268
·
IF 3.784
Qi Zhang,Ruilin Zheng,Jianyong Ding,Peng Cui,Zhongyue Wang,Peng Lv,Wei Wei
Thermally robust and highly efficient green-emitting luminescent ceramics are gradually attracting great attention as promising phosphors using in high-brightness laser phosphor display to reduce serious speckle noise as well as high cost. However, lumen density is still seriously restricting their potential applications especially under high-power density laser due to insufficient absorption of blue laser and significant thermal quenching. Here, we report an Al 2 O 3 -LuAG: Ce composite ceramic phosphor (CCP) for high-brightness laser phosphor display. Owing to good optical properties and high thermal conductivity of Al 2 O 3 , the Al 2 O 3 -LuAG: Ce CCP shows high photoluminescence quantum yield (79.6%), low thermal quenching (only 3.2% loss in luminescence at 200°C), and high thermal conductivity (18.9 W·m −1 ·K −1 ). Moreover, the Al 2 O 3 , as scattering centers, enhances the Rayleigh–Mie scattering of the blue laser, and hence the absorption of the Al 2 O 3 -LuAG: Ce CCP exhibits a remarkable improvement (~2.3 times) at 450 nm. Finally, with optimized thickness (0.3 mm) of Al 2 O 3 -LuAG: Ce CCP, an excellent luminous efficiency (216 lm·W −1 ) and outstanding lumen density (6129 lm·mm −2 ) of the green-emitting light source was obtained by driving under a high-power density (28.33 W·mm −2 ) blue laser. All of those validate the suitability of the Al 2 O 3 -LuAG: Ce CCP for high-brightness display.
研究领域:
材料科学
·
光学工程
·
光子学
·
显示技术
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DOI
高影响因子
危险品化学品经营许可证（带存储）