Materials
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2022
·Vol. 15
·期 8
·2757
·
IF 3.748
Yun Liu,Long Ma,Runa Dong,Kexin Cui,Yongzhao Hou,Wen Yang,Yeqing Liu,Cheng Zhong,Guangwu Wen,Lijuan Zhang
Cf/C-SiC composites have become the preferred material for high-temperature load-bearing applications because of their low density, high strength, and excellent thermal-physical properties. Due to the composite’s poor sintering performance, the sintering temperature and pressure required for the preparation of Cf/C-SiC by traditional methods are also relatively high, which limits its engineering application. Herein, based on the precursor-derived ceramic route and C/C composites material preparation process, a binary binder (coal pitch and polysilylacetylene) is developed, which combines a carbon source, SiC precursor, and semi-ceramic SiC filler organically. Then, the SiC phase was successfully introduced into C/C composites by the slurry impregnation-hot pressing sintering method. The prepared Cf/C-SiC composites showed good mechanical properties, with a density of 1.53 g/cm3and a bending strength of 339 ± 21 MPa. Moreover, the effects of the binary binder on the microstructure, density, and mechanical properties of Cf/C-SiC composites were investigated. This work provides a novel and effective approach to fabricating Cf/C-SiC composites with low density and high strength.Keywords:Cf/C-SiC composite;binary binder;SiC precursor;coal pitch
研究领域:
材料科学
·
复合材料制备
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产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Xishi Wu,Tongzhou Chen,Bijie Wang,Yujie Song,Qing Huang,Zhengren Huang
In this study, novel polyborosilazane-derived SiBCN(O) ceramic was used as self-healing component in self-healing C f /SiBCN(O) composite, which was prepared by polymer infiltration and pyrolysis (PIP) process. Molecular-level structure design of boron-containing ceramic precursors was utilized to achieve uniform dispersion of boron-containing self-healing components in prepared composites. No elemental diffusion was observed at the interface of ceramic matrix and carbon fibers, which resulted in stable SiBCN(O) structure. In addition, boron was uniformly distributed in C f /SiBCN(O) composite ceramic matrix , which was beneficial for self-healing of cracks. Cracks and indentations were able to heal at high temperatures in air. The best crack-healing behavior occurred in air atmosphere at 1000 °C, with nearly complete crack healing. This excellent self-healing behavior was achieved because silicon and boron atoms in SiBCN(O) ceramic reacted with available oxygen at high temperatures to form SiO 2 (l), B 2 O 3 (l), and B 2 O 3 ·xSiO 2 liquid phases, which effectively filled cracks. In general, as-prepared C f /SiBCN(O) composite exhibited excellent self-healing properties and shows great application potential in high-temperature environment applications such as aviation, aerospace, and nuclear power.
研究领域:
材料科学
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航空航天工程
✓ 已验证
产品关联
DOI
高影响因子
INORGANIC CHEMISTRY
·
2022
·
IF 5.436
Xuliang Pang,Huaiquan Zhao,Yifei Huang,Youchao Liu,Hongye Bai,Weiqiang Fan,Weidong Shi
Achievement of the intrinsic activity by in situ electrochemical reconstruction has been becoming a great challenge for designing a catalyst. Herein, an effective electrochemical strategy is proposed to reconstruct the surface of the CF–CuO/CeO2 precursor. Under the stimulation of oxidative/reductive potential, abundant active sites were successfully generated on the surface of CF–CuO/CeO2. Remarkably, the implantation of oxygen vacancy-rich CeO2 synergistically optimizes the chemical composition and electronic structure of CF–CuO/CeO2, greatly promoting the generation of active species. Systematic electrochemical experiments indicate that the superior catalytic performance of reconstructed CF–CuO/CeO2 could be attributed to CuOOH/CeO2 and Cu2O/Ce2O3 active species, respectively. The oxidative-/reductive-activated CF–CuO/CeO2 was further employed in a paired cell for the synergistic catalysis of hydroxymethylfurfural oxidation with 4-nitrophenol hydrogenation. As a result, nearly 100% Faraday efficiency for furandicarboxylic acid/4-aminophenol production was achieved in the paired system (−0.9 V vs Ag/AgCl, 1.5 h). Therefore, the electrochemical reconstruction via oxidative/reductive activation has been confirmed as a feasible approach to significantly excite the intrinsic activity of a catalyst.
研究领域:
材料科学
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电化学
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催化反应
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2019
·Vol. 54
·期 24
·14728-14741
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IF 3.442
Pan Lei,Wang Fei,Pang Xiaofei,Zhang Lei,Hao Jianxiong
In this study, a durable, reusable, effective and large-area molding method was proposed to fabricate hierarchical structures on the CF/PEEK composite surface. The hierarchical structures were fabricated using a combination of sandblasting and anodizing treatments on the metal surface. Subsequently, a hot-pressing process was adopted for producing structures that matched the metal templates. The rough surface was modified by (Heptadecafluoro-1,1,2,2-tetradecyl)trimethoxysilane with low surface energy to obtain superhydrophobicity. Scanning electron microscopy was utilized to observe the surface morphologies and structure. The chemical composition and roughness were analyzed by FT-IR spectroscopy and the laser microscopy, respectively. Wettability was characterized through contact angle measuring instruments, and static and dynamic sliding contact angles were obtained to be 158.23° and 8.38°, respectively. After the abrasion test, the CF/PEEK composite surface still maintained reasonable mechanical stability. Comparing with the untreated sample, CF/PEEK superhydrophobic surface exhibited excellent anti-icing performance with freezing time increasing from 54 to 514 s at − 20° and icing adhesion strength reducing to 30.5 kPa. Although the fabrication of composite surface with water repellency presented here is useful for anti-icing, it can also be applied in other applications that require superhydrophobic surfaces.
研究领域:
材料科学
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表面工程
✓ 已验证
DOI
高影响因子
CATALYSIS TODAY
·
2018
·
IF 4.667
Yi Li,Suge Zhang,Yugui Han,Shanshan Cheng,Wenping Hu,Jingjing Han,Yanan Li
Ciprofloxacin (CIP) is a pervasive ecosystematic contaminant which is classified as highly effective broad-spectrum antibiotic. In this work, CIP was degraded by a self-prepared ternary Ce 3 ZrFe 4 O 14-x /CF composite cathode (x referred to oxygen vacancies) undergoing the heterogeneous electrocatalytic process. The influences of operating parameters such as pH, applied current and loading capacity, were estimated by removing efficiency. Compared with the pure carbon felt (CF), 3.8 wt% Ce 3 ZrFe 4 O 14-x /CF composite cathode showed the efficient degradation of CIP in broad pH range 3.0–6.0 with 100 mA. The degradation rates reached more than 98.0% at the wide pH range in 3 h, even reached 100% at pH = 3. The results indicated that the Ce 3 ZrFe 4 O 14-x /CF composite emerged a brilliant electrocatalysis in enhancing oxygen active species with converting reactions in Ce 4+ ↔Ce 3+ and Fe 3+ ↔Fe 2+ . For further understanding the ternary Ce 3 ZrFe 4 O 14-x /CF composite electrode, we used SEM, BET, TEM, XRD, XPS, TOC , HPLC–MS, EPR, CV and EIS to characterize and analyze. Also, it was deemed as a prospective cathode to accomplish industrialization for CIP degradation, based on lower energy consumption and wide pH range.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Applied Ceramic Technology
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2022
·Vol. 20
·期 3
·1636-1645
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IF 2.328
Yehong Cheng,Fan Zhang,Denghao Ma,Yixin Zhang,Yaxiong Liu,Yumin An,Anzhe Wang,Ning Hu,Libin Zhao,Wenbo Han
Although C f /ZrB 2 –SiC composites prepared via direct ink writing combined with low-temperature hot-pressing were shown to exhibit high relative density, high preparation efficiency, and excellent flexural strength and fracture toughness in our previous work, their oxidation and ablation resistance at high and ultrahigh temperatures had not been investigated. In this work, the oxidation and ablation resistance of C f /ZrB 2 –SiC composites were evaluated via static oxidation at high temperature (1500°C) and oxyacetylene ablation at ultrahigh temperatures (2080 and 2270°C), respectively. The thickness of the oxide layer of the C f /ZrB 2 –SiC composites is <40 μm after oxidizing at 1500°C for 1 h. The C f /ZrB 2 –SiC composites exhibit non-ablative properties after oxyacetylene ablation at 2080 and 2270°C for >600 s, with mass ablation rates of 3.77 × 10 −3 and 5.53 × 10 −3 mg/(cm 2 s), and linear ablation rates of −4.5 × 10 −4 and −5.8 × 10 −4 mm/s, respectively. Upon an increase in the ablation temperature from 2080 to 2270°C, the thickness of the total oxide layer increases from 360 to 570 μm, and the carbon fibers remain intact in the unaffected region. Moreover, the oxidation and ablation process of C f /ZrB 2 –SiC at various temperatures was analyzed and discussed.
研究领域:
材料科学
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航空航天工程
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2024
·Vol. 21
·期 1
·2407337
·
IF 13
Linlong Xing,Haoran Cheng,Yang Li,Qiang Chen,Chuntai Liu,Changyu Shen,Xianhu Liu
The design and development of high-quality electromagnetic waves (EMW) absorbing materials play a vital role in combating the escalating negative effects of microwave radiation and interference. Herein, MoS 2 @Co/NC@CF fibrous membranes are successfully fabricated by electrospinning technology and carbonization, and a molybdenum disulfide (MoS 2 ) layer is synthesized on the surface of these fibers via hydrothermal method. The seed-assisted growth method not only effectively avoids the accumulation and improves the loading of ZIF-67 particles, so as to ensure that the magnetic components in the fibers are evenly distributed in a wider range, rather than only intermittently present in some sites. Meanwhile, the introduction of semiconductor MoS 2 as the shell further optimizes the impedance matching and improves the EMW absorption performance of the carbon fibrous membranes: the minimum reflection loss (RL min ) is −67.56 dB, and the maximum effective absorption bandwidth (EAB max ) is further expanded to 6.56 GHz (2.1 mm, 11.44–18 GHz). This work provides a feasible method for developing high-efficient EMW-absorbing materials.
研究领域:
材料科学
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电磁学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
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2024
·
IF 4.1
Chen Wang,Peng Shi,Chao Guo,Rui Guo,Jiangyuan Qiu
Cobalt-based oxide CuCo 2 O 4 -loaded CuCo 2 O 4 /carbon felt (CF) composite cathodes were synthesized by hydrothermal deposition of a precursor of Cu/Fe oxides on CF followed by roasting in air. The material serves both catalytic and cathodic dual functions in the heterogeneous electro-Fenton (EF) process. Through XRD (X-ray diffraction), FTIR (Fourier transform infrared spectroscopy), XPS (X-ray photoelectron spectroscopy), SEM (scanning electron microscope), and catalytic experiments, it was concluded that CuCo 2 O 4 loading was successful and the highest hydrophilic 180-CuCo 2 O 4 /CF was obtained by varying the hydrothermal temperature without destroying the original structure. 180-CuCo 2 O 4 /CF accomplished 98.03 % degradation in 60 min, and it was found to maintain high degradation capacity in the pH 3 ∼ 9 range in experiments where the experimental parameters were varied. Compared to monometallic oxides, Cu and Co dual active centers are integrated in CuCo 2 O 4 , giving it diverse redox properties and oxidation states. As a result, the CuCo 2 O 4 /CF material can realize the dual function of catalytic and cathodic, which provides a new development direction in practical wastewater treatment.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
CARBON
·
2024
·
IF 10.5
Guangda Guo,Fang Ye,Laifei Cheng,Yucong Wei,Xu Chen
C f /SiC-ZrC renowned for its outstanding performance as a thermal protectant, has gaining widespread recognition. Recent research on this system has emphasized the development of a cost-effective and reusable version with increased thickness for extended use in thick-walled thermal structural components. Ablation resistance, high strength retention, and high thermal conductivity are crucial for successful aircraft reentry. In this study, a low-cost reactive melt infiltration (RMI) method is developed for preparing dense and high-performance large-thickness C f /SiC-ZrC (L-C f /SiC-ZrC) with a gradient-structured matrix. The use of a fine weave-pierced fabric preform structure enhances both the structural integrity and thermal conductivity of C f /SiC-ZrC in the thickness direction. Simultaneously, the gradient-structured matrix, with appropriate contents of surficial ZrC and SiC exhibits erosion resistance, where the internal core with a high SiC content ensures remarkable strength retention. This unique matrix-structure design is achieved by integrating porous C with a single-stage pore structure and a high degree of graphitization degree, and a Si-Zr alloy with a unique composition. The 20mm thick C f /SiC-ZrC obtained via RMI has a density of 2.79 g/cm 3 with an open porosity of 5.65% and flexural strength of 224.3±5.4 MPa. Under a heat flux of 4.186 MW/m 2 , C f /SiC-ZrC exhibits an ablation rate of −0.004 mm/s after 60 s, demonstrating its resilience against ablation damage. Moreover, the post-ablation strength (166.0±4.4 MPa) exceeds that of reported C f /SiC-ZrC congeners, highlighting the robust load-bearing capability.
研究领域:
材料科学
·
航空航天工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Energy Materials
·
2022
·
IF 6.959
Guangzhou Hu,Wenying Fu,Yuxiao Lin,Yuanchao Yue,Maosen Wang,Pengbo Liu,Yinwei Li,Jianwei Li,Lu Wei,Xinsheng Zhao,Yongsheng Wei
Electrochemical water splitting to produce clean hydrogen (H2) and oxygen (O2) has emerged as an advanced technology to build a sustainable society. Low-cost electrocatalysts with excellent performance are required to improve the energy efficiency in overall water splitting. Here, a Co-W-B-P/CF catalyst with a nanoflower-like structure consisting of microspheres and nanoflakes was successfully synthesized using a one-step double-pulse electrodeposition approach. When used as a bifunctional electrocatalyst for overall water splitting, Co-W-B-P/CF presented the potentials of 1.57 and 1.86 V at current densities of 10 and 100 mA cm–2 in 1.0 M KOH solution, respectively. This was even comparable to that of the high-cost commercial catalyst Pt/C(−)//IrO2(+). Detailed electrochemical tests also showed that the kinetics, electron transfer, and intrinsic electrocatalytic activity of Co-W-B-P/CF in the HER (hydrogen evolution reaction) and the OER (oxygen evolution reaction) were dramatically improved due to the synergetic effect of co-doped B and P elements. Considering the excellent electrocatalytic performance of Co-W-B-P/CF, along with the simple synthesis method and low cost, bifunctional electrocatalyst Co-W-B-P/CF for overall water splitting is promising.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
International Journal of Applied Ceramic Technology
·
2024
·
IF 1.8
Pengju Chen,Peng Xiao,Tian Tian,Yang Li
Ytterbium silicate (Yb 2 Si 2 O 7 ) and lanthanum zirconate (La 2 Zr 2 O 7 ) ceramic powders were synthesized by the sol–gel method. A novel tri-layer La 2 Zr 2 O 7 /Yb 2 Si 2 O 7 /SiC environmental barrier coating was prepared on the surface of C/SiC composites to improve the service temperature of the coating (above the Si melting point, 1683 K). Results show that both Yb 2 Si 2 O 7 and La 2 Zr 2 O 7 ceramic powders had extremely high purity and were accompanied by a large number of nanoparticles. The tri-layer La 2 Zr 2 O 7 /Yb 2 Si 2 O 7 /SiC coating can efficiently prevent the oxidation failure of C/SiC composites in 1773 K air environment for more than 100 h with slight weight loss of 5.71 × 10 −3 g·cm −2 and the matching weight loss rate of 5.71 × 10 −5 g·cm −2 ·h −1 . No significant chemical reaction was observed between Yb 2 Si 2 O 7 middle and La 2 Zr 2 O 7 outer coatings during the oxidation process at 1773 K, indicating that the tri-layer La 2 Zr 2 O 7 /Yb 2 Si 2 O 7 /SiC coating had better oxidation stability in 1773 K air environment.
研究领域:
材料科学
·
涂层技术
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Lan Long,Yuting Zhang,Henghai Zhu,Yang Li,Wei Zhou
Reliability and stability of electromagnetic wave absorption (EMA) materials used in high-temperature fields such as aircraft and aero-engines are of great interest. In this regard, the C f /mullite composites with an opportune heterogeneous interface were fabricated using gel-casting and pressureless sintering techniques. The as-prepared composites exhibited excellent EMA performance with multiple relaxation behavior upon increasing testing temperature ranging from 25 °C to 800 °C (the minimum reflection loss (RL min ) of −62.67 dB with a thin thickness of 2 mm at 600 °C). The results demonstrated that the temperature-dependence complex permittivity with multiple relaxation characteristics plays a key role for the EMA performance evolution. The newly generated Cole-Cole semicircle and κ curves with an increasing number of intersections at zero values suggest that the polarization relaxation is enhanced with rising temperatures, thus improving the EMA capacity . It is believed that the C f /mullite composite could be a new promising EMA material at high temperatures.
研究领域:
材料科学
·
电磁学
✓ 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）