POLYMER DEGRADATION AND STABILITY
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2020
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IF 4.032
Tian Liu,Xingrong Zeng,Xuejun Lai,Hongqiang Li
Novel platinum–thiol catalytic system was constructed by the combination of platinum (Pt) catalysts (Karstedt's catalyst (KC) and chloroplatinic acid hexahydrate (CPA)) and thiol-containing compounds ((3-mercaptopropyl)trimethoxysilane (SM), (3-mercaptopropyl)triethoxysilane (SE), 1,6-hexanedithiol (HDT) and 1-octadecanethiol (OT)). It was found that Pt-thiol catalytic system could remarkably enhance the organic-to-inorganic conversion of polydimethylsiloxane (PDMS) and methylvinylpolysiloxane (Vi-PDMS) at elevated temperature. Under optimal condition, the ceramic yield of KC/SE/Vi-PDMS with 50 ppm Pt (KC) and 0.5 phr SE at 1000 °C was dramatically improved from 0.6 wt% to 54.4 wt% in comparison with Vi-PDMS. FTIR , Raman spectroscopy , XPS and XRD revealed that amorphous free carbon-containing SiOC ceramics were formed after thermal treatment of KC/SE/PDMS and KC/SE/Vi-PDMS at 1000 °C for 60min. And during organic-to-inorganic conversion of Vi-PDMS under high temperature, Pt-thiol catalytic system can efficiently retain C in the inorganic network of SiOC ceramics with existence of vinyl. TG , TG-FTIR and viscosity test results suggested that Pt-thiol system might enhance radicals coupling of Vi-PDMS chains and suppress unzipping decomposition or random scission, which resulted in the high capacity of organic-to-inorganic conversion of KC/SE/Vi-PDMS at elevated temperature.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
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2026
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IF 6
Xiumei Wu,Jianwei Teng,Yunping Li,Shu Yu
Hafnium (Hf)-modified silicon oxycarbide (SiOC) ceramics were prepared by preceramic polymer pyrolysis using dimethyldimethoxysilane and methyltrimethoxysilane as precursors and hafnium acetylacetonate as a modifier, followed by spark plasma sintering (SPS). The structural evolution of SiHfOC ceramics with various Hf/Si molar ratios (0–0.08) and the oxidation behavior of SPS-densified ceramic bulks in air at 1500 °C were systematically investigated. From C0Hf to C0.05Hf, the oxide layer evolved from a cracked SiO 2 -rich layer into a thinner and more continuous Hf-Si-O composite layer containing more uniformly distributed HfSiO 4 particles. After oxidation for 32 h, C0.05Hf exhibited the lowest mass loss of 0.195 mg/cm 2 and the smallest oxide-layer thickness of 8.1 μm. Nanoindentation results further indicated improved resistance of the oxide layer to local deformation. The increased formation and more uniform distribution of HfSiO 4 phase reduced cristobalite-related phase transformation strain and thermal-expansion mismatch while enhancing the barrier effect against inward oxygen transport. By contrast, excessive Hf content (Hf/Si molar ratio = 0.08) led to the rapid development of an HfSiO 4 -rich outer region, accompanied by bubble growth, rupture pits, and local spallation, which damaged the integrity of the oxide layer. These results indicate that the Hf-content-dependent phase constitution and oxide-layer architecture govern the oxidation behavior of SiHfOC ceramics at 1500 °C.
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DOI
高影响因子
CERAMICS INTERNATIONAL
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2019
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IF 3.45
Lai Wei,Jing Li,Shuai Zhang,Bo Li,Yu Liu,Feng Wang,Shixiang Dong
In this study, polysiloxane resin was modified at the molecular scale to make it amenable to ultraviolet-curing and suitable for direct ink writing . The characterization results regarding the rheological properties and infrared spectra demonstrated that the conversion of C C is proportional to the viscosity and modulus of ink. As a result, three-dimensional cellular structures with a certain span and tailored porosity were obtained. The printed structures were then subjected to pyrolysis at temperatures higher than 1000°C to form uniform, crack-free, dense SiOC cellular ceramic structures, with ceramic yield of up to 70% and linear shrinkage as low as 25%. This technique enables the inexpensive and fast fabrication of SiOC ceramic products with relatively complex shapes.
研究领域:
材料科学
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制造工程
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产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
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2017
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IF 3.387
Nan Wu,Lynn Yuqin Wan,Yingde Wang,Frank Ko
Hydrophobic ceramic nanofibrous membranes have wide applications in the fields of high-temperature filters, oil/water separators, catalyst supports and membrane reactors, for their water repellency property, self-cleaning capability, good environmental stability and long life span. In this work, we fabricated an inherently hydrophobic ceramic nanofiber membrane without any surface modification through pyrolysis of electrospun polycarbosilane nanofibers. The hydrophobicity was introduced by the hierarchical microstructure formed on the surface of the nanofibers and the special surface composition by the addition of trace amounts of palladium. Furthermore, the flexible ceramic mats demonstrated robust chemical resistance properties with consistent hydrophobicity over the entire pH value range and effective water-in-oil emulsion separation performance. Interestingly, a highly cohesive force was found between water droplet and the ceramic membranes, suggesting their great potentials in micro-liquid transportation. This work provides a new route for adjusting the composition of ceramic surface and flexible, recyclable and multifunctional ceramic fibrous membranes for utilization in harsh environments.
研究领域:
材料科学
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环境工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2024
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IF 5.8
Jimei Xue,Yuan Gao,Fei Li,Yuqiu Wang,Cunxian Wang,Fan Yang,Xiaomeng Fan,Laifei Cheng
Oxide ceramic matrix composites (OCMC) are extensively used as thermal structural materials due to good high-temperature resistance, mechanical properties, and oxidation resistance, but they are rarely regarded as electromagnetic wave absorbing materials due to the high resistivity of oxide ceramics/fibers. However, high-performance Al 2 O 3 fiber can be used to design and fabricate OCMC with integrated high-temperature microwave absorbing and mechanical properties by introducing dielectric material into Si-based ceramic matrix. The N610/Si 3 N 4 -SiOC composites have the prior mechanical performance because the uniformly distributed Si 3 N 4 matrix made the fiber bear effectively. After that, the Sc 2 O 3 modified SiOC matrix was filled into inter- and intra-fascicular pores forming interfacial polarization, dipole polarization, multiple reflection and scattering to attenuate the incident electromagnetic wave (EMW). The effective absorption bandwidth (EAB) and the minimum reflection coefficient (RC min ) of N610/Si 3 N 4 -SiOC(Sc) composites at the thickness of 2.75 mm reach 3.0 GHz and −42 dB in the X band, respectively. In addition, the EMW absorption performance of the composite is relatively stable with EAB max and RC min of 3.5 GHz and −41 dB in 4–18 GHz at high temperatures. This work provides a strategy for designing and fabricating OCMC with excellent mechanical properties and EMW absorption properties.
研究领域:
材料科学
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电磁学
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE
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2026
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IF 2.6
Liu Qidong,Wu Xiumei,Peng Yukang,Li Yunping,Yu Shu,Xiao Zian
SiZnOC gels were coated on C/C substrate by sol–gel, using methyltriethoxysilane (CH 3 Si(OCH 2 CH 3 ) 3 , MTES) and dimethyldiethoxysilane ((CH 3 ) 2 Si(OCH 2 CH 3 ) 2 , DMDES) as precursors, and zinc acetylacetonate (Zn(acac) 2 ) as the modifier. After pyrolysis under argon at 700 °C, SiZnOC ceramics were obtained. Microstructures of SiZnOC with different Zn/Si molar ratios were characterized by FTIR, XRD, SEM and XPS. Biocompatibilities of SiZnOC ceramics were measured by MTT, cell adhesion, antimicrobial activity of Escherichia coli and Staphylococcus aureus, DPPH free radical scavenging and reactive oxygen species (ROS) levels. Vitro bioactivities of materials were evaluated by the generation of bone-like hydroxyapatite (HA) in simulated body fluid (SBF). Results showed that antibacterial and antioxidant properties of SiZnOC enhanced with the content of Zn doping. When Zn:Si molar ratio of SiZnOC increased to 0.4, the inhibition zone diameters were the biggest of 6.7 mm and 5.4 mm for E. coli and S. aureus, respectively, and the scavenging rate was the highest of 88.9% for the DPPH free radicals. However, the level of intracellular reactive oxygen species (ROS) expression was promoted with the increase of Zn doping either. SiOC with Zn:Si molar ratio of 0.2 has the quickest speed of generation bone-like hydroxyapatite (HA) in SBF, on the balance of biocompatibility, bioactivity and antimicrobial performance, SiZnOC with Zn:Si molar ratio of 0.2 was the best for the moderate antimicrobial and antioxidant properties, and the qualified biocompatibility.
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产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
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2026
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IF 19.9
Xiaocheng Huang,Weiwei Du,Xianglin Wang,Pengzhe Cai,Yuanhao Shen,Bingqing Wei,Qifeng Zhao,Chunxiao Li,Delong Liu,Zheng Yang,Yingwu Luo,Zhenglong Li,Junjie Zhao
Self-aligned patterning via area selective deposition (ASD) is promising for circumventing the overlay variation in photolithography for advanced nanomanufacturing. However, completely reversing the area selectivity when film growth is more favorable on the target non-growth surface (NGS) than the target growth surface (GS) remains a daunting challenge even with etching incorporated. Here, we report an etching amplification strategy for ASD. We identified ring-opening of 1,3,5-trivinyl-1,3,5-trimethylcyclotrisiloxane (V 3 D 3 ) on CoO x surface by in-situ diffuse reflectance infrared Fourier transform spectroscopy. This reaction enhances the plasma etching rate for V 3 D 3 polymer by 243%. In-situ quartz crystal microbalance showed higher mass uptake on target NGS of CoO x than target GS of SiO 2 during deposition, yet plasma etching fully removes adsorbed species on target NGS. Accordingly, we achieved ASD of SiOC film (ca. 18.36 nm thick) with nearly 100% selectivity on pre-patterned Co/SiO 2 substrates. This work sheds light upon etching amplification by precursor isomerization for developing highly selective ASD processes.
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
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2025
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IF 5.6
Jing Li,Jiacheng Li,Yiyang Qiu,Zhangsong Qiu
With the rapid advancement of aerospace and chemical industries, there was an increasing demand for high-performance structural materials that could withstand extreme high-temperature environments. Ceramic fibers and their composites were investigated as promising candidates due to their low density, high specific strength and modulus, excellent oxidation resistance, and ablation performance, which made them ideal for structural-functional integration under harsh thermal conditions. This study explored the preparation of Hafnium-doped silicon oxycarbide (SiOC) ceramic fibers via emulsion electrospinning, focusing on the influence of key parameters such as water-to-oil (W/O) ratio, spinning voltage, and propulsion speed on fiber morphology and structure. The emulsion method successfully addressed the bottleneck in the fabrication of sub-micron ceramic fibers. The results demonstrated the W/O ratio significantly affects fiber morphology, with lower ratios reducing bead formation and producing more uniform fibers. The optimal spinning voltage was found to be between 12.0 and 15.0 kV, yielding fibers with an average diameter of approximately 320 nm. The fibers exhibited excellent thermal stability, with a weight loss of only 2.38 % after pyrolysis at 800 °C in a nitrogen atmosphere. X-ray diffraction (XRD) analysis confirmed the presence of SiO 2 , SiC, HfO 2 , and HfSiO 4 phases, indicating successful hafnium doping. This study highlighted the potential of emulsion electrospinning as a scalable and environmentally friendly method for producing high-performance ceramic fibers with submicron scale, demonstrating its effectiveness in fabricating ultrathin fibers suitable for high-temperature applications.
研究领域:
材料科学
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陶瓷工程
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纳米纤维制备
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高温材料
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航空航天材料
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2019
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IF 8.355
Zhiyuan Sang,Dong Su,Jinsong Wang,Yue Liu,Huiming Ji
Potassium-ion batteries (PIBs) are considered as promising alternative candidates to replace lithium-ion batteries due to their low cost, adequate reserves and high energy density. However, a large ionic radius of K + ions leads to a huge volume expansion and a low ion diffusion rate, restricting its cycling stability and rate performance. Herein, bi-continuous and nanoporous carbon spheres (BC-NCS), consisting of continuous nanocarbon framework and interconnected nanopores, are designed and prepared by etching carbon-rich SiOC ceramics. The interconnected nanopores provide fast ion diffusion channels and sufficient room for tolerating the volume expansion, thus leading to high rate performance and long cycle stability, while the continuous carbon framework possesses a defective nature, an expanded interlayer distance (0.39 nm) and various oxygen‐containing functional groups on its surface induced during the etching process, further endowing it with high reversible capacity and stability. Therefore, the BC-NCS exhibits a high initial reversible capacity (336 mAh g −1 at 0.1 A g −1 ), long cycle and high rate performance (191 mAh g −1 after 2000 cycles at 0.5 A g −1 ). Importantly, we investigate the potential application of bi-continuous carbon materials in high performance PIBs, and the bi-continuous structure could be induced into various active materials for the application in different batteries.
研究领域:
材料科学
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能源存储
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
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2025
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IF 5.6
Xinlei Jia,Xinqiao Wang,Donghui Guo,Shun Wang,Runze Jin,Ning Zhou,Baosheng Xu
Owing to their excellent thermal insulation properties and chemical stabilities, ceramic aerogels are widely employed in thermal protection structure; however, their potential as electromagnetic wave (EMW) absorbers remains underdeveloped. Aerogels that provide both high-temperature thermal insulation and EMW absorption are difficult to obtain. Herein, a new mullite/SiC/SiOC (MCS) composite aerogel was grown in situ using a sol–gel process with a mullite nanofiber sponge as reinforcement. The pores in the fiber sponge are filled with numerous SiC nanowires and SiOC aerogel, forming a multiscale porous nanostructure. The semiconductor insulator composition and specific nanostructure endow MCS with excellent impedance-matching characteristics and strong EMW loss capability. The minimum reflection loss reaches −35.12 dB at a thickness of 2.5 mm and the effective absorption bandwidth almost covers the X-band. Meanwhile, the composite is lightweight (0.13–0.15 g cm −3 ) with a low thermal conductivity (0.03–0.036 W m −1 K −1 ), offering excellent thermal insulation performance. Overall, MCS composites are promising for applications requiring thermal insulation and EMW absorption.
研究领域:
材料科学
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电磁学
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热能工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2023
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IF 15.1
Zhiwei Chen,Dong Su,Wenxia Zhu,Xiaoliang Sun,Xiaolei Li,Huiming Ji
With the flourishing development in space exploration and human motion detection, the wide-temperature flexible pressure sensors are urgently required in various complex application situations. One massive challenge of current available sensors is to enhance the oxidation resistance property, which is crucial for their applications in high-temperature environments. Herein, we fabricated a superelastic silicon oxycarbide @carbon (SiOC@C) ceramic spring, possessing a porous lamellar and spring-like structure. The spring-like structure tends to deform and absorb the energy under the external loads, and then the anisotropic lamellar structure can effectively and uniformly release the stress. The as-prepared SiOC@C spring exhibits excellent superelasticity, high compressibility (60%), and robustness (∼99.0% maximum stress retention after 1000 cycles at 50% compression). Meanwhile, the SiOC@C spring-derived sensor possesses a high sensitivity under low pressure (282.46 kPa −1 at < 1.3 kPa), a low detection limit (< 0.098 Pa) and a short response/recovery time (∼12 ms/4 ms). Moreover, benefiting from the high/low-temperature resistance of SiOC nanolayer coated on the carbon framework, the SiOC@C spring-based sensor can function properly at a wide temperature range from − 196 °C to 500 °C, showing the potential application in various fields of biomedical monitoring, space exploration, and automotive industries.
研究领域:
材料科学
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传感器技术
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生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
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2019
·
IF 5.155
Kedong Xia,Li Qu,Xiao Liu,Huijuan Han,Zhenyu Hou,Yunling Li,Shaoxin Deng
Sn/SiOC composites with varying Sn content were prepared by the sol–gel method with phenyltriethoxysilane (PhTES) and Tin(II) chloride dihydrate (SnCl 2 ·2H 2 O) as precursors. The effect of SnCl 2 addition on the microstructure, morphology and lithium storage performance of SiOC anodes was investigated. Incorporation of SnCl 2 not only reduces carbon-contained units of SiOC ceramics, but also increases the oxygen-containing functional groups on the surface of carbon during the pyrolysis conversion. The formation of Sn involves carbothermal reduction reaction of SnO 2 with the free carbon, and the degree of carbothermal reduction increases with the increase of Sn/Si ratio, which results in the reduction of carbon content and destruction of SiOC matrix. The size of Sn nanograins increases from 20 nm to 450 nm with the increasing Sn/Si ratio. The rate capability of Sn/SiOC composites increases first and then decreases with the increase of Sn content. The SiOC and Sn-PhTES-0.15 derived Sn/SiOC composite exhibit better electrochemical performance, which delivers a stable reversible capacity of 485 mAh g −1 and 411 mAh g −1 , respectively at 186 mA g −1 after 250 cycles. The uniform dispersed Sn nanograins (below 20 nm), Si O C structure units and the free carbon phase both contribute to better electrochemical properties. However, the free carbon provides a higher reversible capacity than that of Sn and Si O C units, which results in the inferior lithium storage capacity of Sn/SiOC composites.
研究领域:
材料科学
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能源存储
✓ 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）