International Journal of Applied Ceramic Technology
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2023
·Vol. 20
·期 3
·1617-1623
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IF 2.1
Debao Liu,Chao Zhang,Yahui Xue
In this study, the ultralong SiC nanofibers (SiC NFs) were synthesized through the sol–gel method assisted the chemical vapor deposition technique. The scanning electron microscope, transmission electron microscopy, X-ray diffraction, Raman, Fourier transform infrared, and X-ray photoelectron spectroscopy techniques were systematically employed to investigate the microstructure, morphology, and phase composition of the as-prepared products. The results demonstrated that the as-obtained products were β-SiC nanofibers with face-centered cubic crystal structure. Meanwhile, the ultralong SiC NFs present an average diameter of about 18 nm and a length up to several hundreds of micrometers and grew along the [1 1 1] direction with a planar stacking faults. In addition, we also investigated the formation mechanism and growth process of the ultralong SiC NFs. The successful preparation of such ultralong SiC NFs provides new idea for fabricating of other silicon-based ultralong nanofibers.
研究领域:
材料科学
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纳米技术
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产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
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2023
·
IF 5.7
Zhenxiao Tang,Maozhong Yi,Zhe Zhou,Huang Wu,Yuanming Zhou,Ke Peng
A C/C-TaB 2 -SiC composite was successfully prepared by high-solid-loading slurry impregnation combined with polymer infiltration and pyrolysis. The composite had a density of 3.46 g/cm 3 and consisted of pyrolyzed carbon, carbon fibers, TaB 2 particles, and precursor-derived SiC with their mass fractions of 7.8 %, 13.0 %, 58.6 %, and 20.6 %, respectively. The C/C-TaB 2 -SiC composite possessed a flexural strength of 248.2 ± 16.8 MPa and a fracture toughness of 13.7 ± 1.6 MPa·m 1/2 , and demonstrated a non-brittle fracture behavior . After exposure to oxyacetylene flame with a heat flux of 4.18 MW/m 2 for 120 s, the ablation temperature of the sample surface reached a maximum of 2263 °C, and the mass and line ablation rates were 2.24 mg/s and 12.92 µm/s, respectively. The ablation resistance mainly comes from the hindrance of oxygen diffusion by the oxide layer composed of tantalum oxide and a small amount of SiO 2 .
研究领域:
材料科学
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航空航天工程
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
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IF 13.3
Zhi-Yuan Zheng,Zhi-Feng Jiao,Ji-Xiao Zhao,Xin-Chao Liu,Cai-Dong Song,Jia-Hang Li,Xiang-Yun Guo
In the hydrogenation of polyfunctional compounds, achieving high selectivity for specific functional groups remains challenging. Herein we report that SiC quantum dots (QDs) can selectively adsorb C = O in cinnamaldehyde, significantly increasing the activity and selectivity of Pt/SiC for hydrogenating cinnamaldehyde to cinnamyl alcohol. A 10 wt% QDs-modified Pt/SiC catalyst showed a turnover frequency 3.5 times higher than Pt/SiC under mild conditions. Further studies reveal that the defect-rich surface of SiC QDs facilitates the adsorption of C = O bond in cinnamaldehyde and enhances the spillover of active hydrogen from Pt to SiC QDs. During the catalysis process, Pt is responsible for the generation of reactive hydrogen species while the QDs undertake the activation of C = O bond, and the hydrogen species react with cinnamaldehyde via spillover. This work demonstrates the promise of SiC QDs in heterogeneous catalysis and provides a reference for designing novel hydrogenation catalysts.
研究领域:
材料科学
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催化化学
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产品关联
DOI
高影响因子
ACS Applied Energy Materials
·
2025
·
IF 5.5
Hezhang Li,Hualu Zhuang,Jincheng Yu,Bowen Cai,Ruiheng Liu,Yi Niu,Jing Jiang,Jing-Feng Li,Chao Wang
Heusler alloys have attracted increasing attention due to their rich functionalities, among which Co2MnSi, a half-metallic full-Heusler, is expected to be a promising n-type thermoelectric material with a superior power factor. However, the intrinsically high thermal conductivity of Heusler alloys due to their metallic nature limits the enhancement in thermoelectric performance. Therefore, it is crucial to reduce the thermal conductivity while maintaining the high power factor, which is a key strategy to fabricate high-performance Co2MnSi alloys. Here, by incorporating a small amount of SiC nanoparticles into the Co2MnSi matrix, the thermoelectric figure of merit is enhanced by approximately 5-fold from 0.03 to 0.15 at 1025 K, due to a significant reduction in thermal conductivity from 22 to 5 W/mK. The electrical transport properties do not suffer any obvious degradation after incorporation of a significant amount of SiC, while the mechanical strength of Co2MnSi-based alloys is further improved. The thermoelectric device fabricated with Co2MnSi as the thermoelectric legs is validated for solid-state refrigeration. It is also expected to promote the development of Co2MnSi-based thermoelectrics with strong magnetism for new applications with multiple functionalities.
研究领域:
材料科学
·
物理学
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产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
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2018
·
IF 3.794
Qianglong He,Aiyang Wang,Chun Liu,Weimin Wang,Hao Wang,Zhengyi Fu
B 4 C-TiB 2 -SiC composites were fabricated via hot pressing using ball milled B 4 C, TiB 2 , and SiC powder mixtures as the starting materials. The impact of ball milling on the densification behaviors, mechanical properties , and microstructures of the ceramic composites were investigated. The results showed that the refinement of the powder mixtures and the removal of the oxide impurities played an important role in the improvement of densification and properties. Moreover, the formation of the liquid phases during the sintering was deemed beneficial for densification. The typical values of relative density, hardness, bending strength , and fracture toughness of the composites reached 99.20%, 32.84 GPa, 858 MPa and 8.21 MPa m 1/2 , respectively. Crack deflection, crack bridging, crack branching, and microcracking were considered to be the potential toughening mechanisms in the composites. Furthermore, numerous nano-sized intergranular/intragranular phases and twin structures were observed in the B 4 C-TiB 2 -SiC composite.
研究领域:
材料科学
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陶瓷工程
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产品关联
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
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2020
·
IF 4.019
Jingru Wang,Shanhui Zhu,Yunwei Wang,Yingyong Wang,Guoqiang Jin,Xili Tong,Xiangyun Guo
The hydrogenation of levulinic acid (LA) to γ-valerolactone (GVL) under mild condition is a promising but challenging process. Herein, SiC supported Ru-Ir bimetallic catalyst exhibit enhanced catalytic activity for aqueous hydrogenation of LA into GVL under mild conditions. Comparing with monometallic Ir 3 /SiC and Ru 3 /SiC, the conversion of LA over bimetallic Ru 0.5 -Ir 2.5 /SiC catalyst increase from 51.2 % and 45.9% to 100% at 25 °C and 0.2 MPa of H 2 pressure. The enhanced catalytic activity of Ru 0.5 -Ir 2.5 /SiC catalyst originates from the electronic synergistic effect among Ru, Ir and SiC. Due to the electron transfer, electron-richened Ir nanoparticles show stronger ability for H 2 dissociation, and the SiC surface produces more active sites to accommodate hydrogen species that spill over from Ir and Ru. The adsorption and hydrogenation of LA molecules occur on the surface of SiC.
研究领域:
催化化学
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能源化学
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产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2015
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IF 2.605
Konghao Chen,Yixin Hua,Cunying Xu,Qibo Zhang,Cancan Qi,Yafei Jie
TiC/SiC composites were successfully prepared from Ti-enriched slag via an electro-deoxidization process in molten CaCl 2 –NaCl eutectic melt at 700 °C in argon. Electrolysis was conducted at an applied voltage of 3.2 V using a graphite anode and a composite cathode composed of graphite powder and Ti-enriched slag. According to the results, a possible reaction pathway was suggested: firstly the complex Ti-compounds were decomposed into TiO 2 -based simple oxides; then a mass of CaTiO 3 and a spot of CaSiO 3 formed accompanied by the reduction of titanium dioxide to titanium sub-oxide such as TiO, Ti 2 O; finally the graphite powder involved in the formation of SiC, TiC 1− x O x , which were further converted into SiC and TiC by prolonging electrolysis.
研究领域:
材料科学
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电化学工程
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产品关联
DOI
高影响因子
OPTICAL MATERIALS
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2024
·
IF 3.8
Mengyao Xue,Jingwei Han,Xing Dai,Yucai Ge,Yunhua Zhang,Zibin Hai
Cu 2 O–SiC/g-C 3 N 4 composite photocatalysts with excellent photocatalytic performance under visible light were synthesized for the first time via a facile approach combining calcination with hydrothermal reaction. Comprehensive characterization of the synthesized samples encompassing composition, morphology, structure and photoelectric properties was conducted utilizing techniques such as X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), diffuse reflectance spectroscopy (DRS), photoluminescence spectroscopy (PL), and electrochemical impedance spectroscopy (EIS). Results unequivocally demonstrate successful preparation of the ternary composite through Cu 2 O loading onto SiC/g-C 3 N 4 , evincing markedly elevated activity compared to individual counterparts and binary composites. Notably, in the presence of the prepared Cu 2 O–SiC/g-C 3 N 4 , the degradation rate of methyl orange reached 93.70 % under illumination with a visible LED light rated at 5 W. The notable enhancement in photocatalytic performance of the ternary composites is primarily ascribed to the synergistic effects stemming from the formation of p-n junctions between Cu 2 O and g-C 3 N 4 , alongside the Z-scheme configuration established between Cu 2 O and SiC. Free radical quenching experiments corroborated •O 2 − and h + as the principal redox species mediating the visible light quenching process. This study not only presents a feasible strategy for the fabrication of Cu 2 O-based ternary composites with significantly augmented photocatalytic performance but also delineates a novel avenue for the design and construction of composite photocatalysts facilitating enhanced charge-carrier generation and separation concomitantly.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2019
·
IF 4.029
Xiaorong Zhang,Zhixiao Zhang,Yuming Liu,Aiyang Wang,Shi Tian,Weimin Wang,John Wang
In this work, we systematically studied the effects of powder characteristics (B 4 C, TiC and Si powders) on the existential form of toughening phases (SiC and TiB 2 ) as well as the overall microstructure and properties of B 4 C–TiB 2 –SiC composites fabricated by reactive hot pressing. The particle size of the TiC powder plays a largely determining role in the development of novel toughening phases, the TiB 2 –SiC composite structure, that are formed in the B 4 C matrix, while the Si particle size affects the agglomerate level of the SiC phase. The TiB 2 –SiC composite structure and SiC agglomerates enhance the fracture toughness, but decrease the flexural strength . Both the microstructure and mechanical properties of B 4 C–TiB 2 –SiC composites can be effectively tuned by regulating the combinations of the particle sizes of the starting powders. The B 4 C–TiB 2 –SiC composites demonstrate flexural strength, fracture toughness and Vickers hardness in the respective range of 567–632 MPa, 5.11–6.38 MPa m 1/2 , and 34.8–35.6 GPa.
研究领域:
材料科学
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机械工程
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产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
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2020
·
IF 4.495
Yushi Qi,Kai Jiang,Changling Zhou,Wenbo Han,Zhiming Du
The development of novel cermet composites based on porous ceramics with high porosity, interconnected pore structure and good mechanical property has attracted considerable attention in engineering application. In this work, water-based freeze casting process was employed to fabricate ZrB 2 -SiC porous ceramic with aligned lamellar-channels structure using PAA-NH 4 as the dispersant. The results revealed that the well-dispersed suspension with best rheological behavior was obtained using 1.0 wt% PAA-NH 4 at pH 9. The crack-free porous ceramic exhibited small volume shrinkage ranging from 2.59 % to 1.87 %. By varying the solid loading, the fabricated samples displayed a tailored porosity ranging from 76.12% to 59.37% and an excellent compressive strength of 7 MPa to 78 MPa. After oxidation, the samples displayed a decreased porosity and an increased compressive strength. The ZrB 2 SiC porous ceramic fabricated in this work will be a promising candidate for the framework of cermet composite.
研究领域:
材料科学
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陶瓷工程
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS
·
2013
·
IF 1.858
Rubing Zhang,Rujie He,Xinghong Zhang,Daining Fang
ZrB 2 –SiC ceramic composites were prepared through water-based gelcasting and pressureless sintering. Effects of the pressureless sintering temperature (1500–2000 °C), heating rate (5–15 °C/min) and soaking time (0.5–2 h) on the relative density, microstructure and mechanical properties of the ZrB 2 –SiC composites were investigated in detail. A sintering temperature of 2000 °C, a heating rate of 5 °C/min and a soaking time of 2 h were found to be the optimal pressureless sintering procedure. The relative density, flexural strength and fracture toughness of the ZrB 2 –SiC composite prepared under the optimum condition were 97.8%, 403.1 ± 27.8 MPa and 4.05 ± 0.42 MPa·m 1/2 , respectively.
研究领域:
材料科学
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陶瓷工程
✓ 已验证
DOI
高影响因子
CATALYSIS COMMUNICATIONS
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2020
·
IF 3.612
Jingru Wang,Yingyong Wang,Xili Tong,Yunwei Wang,Guoqiang Jin,Xiangyun Guo
A 3 wt% Ir/SiC catalyst prepared by the wet impregnation method showed excellent catalytic activity and stability for the aqueous hydrogenation of levulinic acid (LA) to γ-valerolactone (GVL) in a batch reactor system. LA was completely converted to GVL at 50 °C and 0.2 MPa of H 2 pressure with 100% selectivity and a high turnover frequency (TOF) of 333 h −1 . The high activity of Ir/SiC catalyst could be related to the Schottky-type contact between Ir and SiC solid phases, which promotes electron transfer between support and metal. Due to the excellent acid resistance of SiC support, the Ir/SiC catalyst showed high catalytic stability and nearly no loss of activity after 5 consecutive catalytic operation cycles.
研究领域:
化学工程
·
催化科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）