CERAMICS INTERNATIONAL
·
2017
·
IF 2.986
Wenhu Hong,Shun Dong,Ping Hu,Xiaoguang Luo,Shanyi Du
Enhanced microwave absorption properties of porous PDC-SiC/Si 3 N 4 ceramics were successfully prepared through in situ growth of Si 3 N 4 nanowires (NWs) by the unidirectional freeze casting of Si 3 N 4 /camphene slurries with various polycarbosilane (PCS) contents at 1400 °C in N 2 . Si 3 N 4 NWs were in situ formed in the pore channels via a vapor-solid (VS) mechanism, the content of Si 3 N 4 NWs increased with increasing of PCS content, which tailored the microstructure and mechanical property of porous PDC-SiC/Si 3 N 4 ceramics. With the increase of PCS content, the minimum reflection coefficient (RC) of porous PDC-SiC/Si 3 N 4 ceramic decreased from −20.2 dB to −56.2 dB, and the effective absorption bandwidth (EAB) increased from 5.3 to 7 GHz, demonstrating that the porous PDC-SiC/Si 3 N 4 ceramics decorated with Si 3 N 4 NWs had a superior microwave-absorbing ability, which could be ascribed to the electronic dipole polarization and interfacial scattering enhanced by the various interfaces among Si 3 N 4 , in-situ formed PDC-SiC nanograins, nanosized carbon and Si 3 N 4 NWs phases. These findings provide significance guidance in the development of new broadband EM absorbing materials.
研究领域:
材料科学
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电磁学
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产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2022
·
IF 7.392
Mingshuai Sun,Fumin Wang,Guojun Lv,Xubin Zhang
S-containing silane coupling agents (SCA) with various structures were chosen as regulators to synthesize PdC nanoparticles in different sizes for semi-hydrogenation of acetylene. Characterization and catalytic performance demonstrate that the catalytic property of PdC is deeply influenced by particle size. PdC particles prepared by employing SCA containing sulfhydryl has a smaller size and narrow diameter distribution. They exhibited better inhibition on ethane formation than those by containing thioether bond. Catalysts with larger PdC particles have lower selectivity to C4 and green oil. Reaction paths on typical (1 1 1) surface of PdC nanoparticles with different dimensions were investigated by DFT calculations. It reveals that within a certain particle size range (∼2.6 nm), surfaces of smaller PdC particles have weaker adsorption strength of ethylene. As particle size exceeds 2.6 nm, the adsorption strength no longer increases. C4 and green oil are more likely to be generated when PdC particles are around 2 nm, and the size smaller or larger than 2 nm will weaken the tendency of C4 and green oil formation.
研究领域:
催化化学
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材料科学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Wen Yang,Chong Liu,Yongzhao Hou,Xiangjun Dai,Cheng Zhong,Yongqiang Ma,Meixian Jiang
In this work, a novel carbon-enriched SiC by the polymer derived ceramic (PDC-SiC) route was manufactured. By varying the branched chain of the preceramic polymer, the structure and electromagnetic properties of the obtained PDC-SiC ceramics can be effectively altered through carbon enrichment. Specially, PDC-SiC ceramics obtained from branched polysilylacetylene (PSA) constitute a composite material that contains nano-sized SiC grains, carbon nanotubes (CNTs), and silicon carbide nanowires (SiC nw ). Such PDC-SiC ceramics possess a complex three-dimensional network of CNT S /SiC nw , leading to remarkable microwave absorption properties. Notably, the PDC-SiC ceramics processed from dimethyl-polysilylacetylene (D-PSA) achieved a minimum reflection loss (RL min ) of −55.0 dB at 14.4 GHz, and an effective absorption bandwidth (EAB) extends across 5.5 GHz, with a thickness of 2 mm.
研究领域:
材料科学
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电磁学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2021
·
IF 4.311
Mingshuai Sun,Fumin Wang,Jiaqi Hu,Guojun Lv,Xubin Zhang
A highly dispersed and stable PdC phase supported on α-Al 2 O 3 for semi-hydrogenation of acetylene was prepared using N-containing silane coupling agent as a modifier. The catalyst exhibited as much as 15% higher ethylene selectivity than traditional PdAg alloy with full acetylene conversion under 240 °C and performed longer stability within 200 h tolerance test. Characterization results reveal that the excellent ethylene selectivity is mainly derived from the special PdC phase nanoparticle structure with lattice relaxation and distortion. This unique structure makes the catalyst perform weaker adsorption of ethylene, have more abundant spillover hydrogen on the carrier surface and lead a strong interaction between the Pd nanoparticles and surface. Experimental results and DFT calculations have shown the PdC phase is a more promising structure than the commonly used PdAg alloy.
研究领域:
催化
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材料科学
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化学工程
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产品关联
DOI
高影响因子
ENERGY
·
2026
·
IF 10.1
Lirong Li,Jiaying Wu,Zhiping Xiao,Chengwei Xu,Chuang Meng
The high energy consumption of CO 2 capture technologies stems largely from the limited efficiency of the adsorbents and the energy-intensive regeneration process, posing a major barrier to large-scale deployment. This study provides a robust material solution through the first synthesis and energetic evaluation of a stable CAU-10-PDC metal-organic framework, marking a significant step beyond its previously conceptualized membrane forms. By substituting the original benzene-dicarboxylate linkers in CAU-10 with pyridine-3,5-dicarboxylate ligands, we engineered a framework with tailored 4.15 Å pore channels that exhibits exceptional thermal stability up to 397 °C and a high BET surface area of 896.9 m 2 /g. The material achieves high CO 2 uptake of 5.05 mmol/g at 273 K and 4.01 mmol/g at 298 K, along with outstanding cyclic stability (>99.9% capacity retention over 10 TVSA cycles). Multiscale simulations further reveal a low isosteric enthalpy of 26.25 kJ/mol, confirming an energy-efficient physisorption mechanism. This low regeneration energy requirement, coupled with the identification of preferential CO 2 binding at pyridinic nitrogen sites (binding energy: −8.44 kJ/mol), positions CAU-10-PDC as a promising candidate for next-generation CO 2 capture systems like direct air capture (DAC). Our work provides the first comprehensive dataset for CAU-10-PDC and offers an atomistic blueprint for designing high-performance, low-energy adsorbents.
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DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
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2020
·Vol. 103
·期 8
·4063-4068
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IF 3.502
Bin Du,Honghua Liu,Yanhui Chu
Polymer-derived ceramic (PDC) route has been widely used to fabricate various ceramics or ceramic-matrix composites in recent years. However, the synthesis of high-entropy ceramics via PDC route has rarely been reported until now. Herein, we successfully synthesized a class of high-entropy carbides, namely (Hf 0.25 Nb 0.25 Zr 0.25 Ti 0.25 )C (HEC-1), via PDC route. The polymer-derived HEC-1 ceramics consisted of numerous superfine particles with the average particle size ~800 nm. Meanwhile, they possessed a rock-salt structure of metal carbides and high-compositional uniformity from nanoscale to microscale. In addition, the as-obtained HEC-1 ceramics had a low oxygen impurity content of 0.51% and a low free carbon impurity content of 2.56%. This work will open up a new research field on the fabrication of high-entropy ceramics or high-entropy ceramic-matrix composites via PDC route.
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
Arabian Journal of Chemistry
·
2018
·
IF 2.969
Shuai Zhang,Shoulian Wei,Hao Cheng,Wei Li
Nano-scaled Fe 3 O 4 were synthesized using solvothermal synthesis, and amino-modification of nano-scaled Fe 3 O 4 was conducted with APTES. With Fe 3 O 4 -NH 2 and Zn 2+ as the metal centers, 2,6-pyridinedicarboxylic acids as the organic ligand, and using the one-step ultrasonic-assisted method, a new magnetic zinc pyridinedicarboxylic acid nanocomposite (Zn-(PDC) 2 @Fe 3 O 4 ) was synthesized. The structure, composition and morphology of the products were characterized using methods such as X-ray single crystal diffraction, Fourier transform infrared spectroscopy (FTIR), X-ray powder diffraction, and scanning electron microscope. The results showed that the Zn-(PDC) 2 was almost an octahedron, and the Zn-(PDC) 2 @Fe 3 O 4 looked like a nanoflower. The mimetic peroxidase properties of Zn-(PDC) 2 @Fe 3 O 4 were studied with H 2 O 2 solution and TMB solution as the substrates, and the results showed that: the Michaelis constant of H 2 O 2 by Zn-(PDC) 2 @Fe 3 O 4 was: K m = 0.411 mM, the maximum reaction rate: v max = 3.440 × 10 −8 M s −1 ; the Michaelis constant of TMB by Zn-(PDC) 2 @Fe 3 O 4 was: K m = 0.189 mM, and the maximum reaction rate: v max = 2.419 × 10 −8 M s −1 , both of which were lower than those of H 2 O 2 and TMB by Fe 3 O 4 and Horseradish Peroxidase (HRP). Based on the reduction of the absorbance of original solution due to the consumption of H 2 O 2 in oxidation-reduction reaction between SO 3 2− and H 2 O 2 under acid conditions, a new method for determining the content of SO 3 2− was established. The linear range of SO 3 2− was 8 × 10 −7 ∼8 × 10 −5 mol/L, the detection limit of SO 3 2− was 8 × 10 −8 mol/L, and the RSD of SO 3 2− was 2.7–9.2%.
研究领域:
材料科学
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生物化学
·
分析化学
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产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Jimei Xue,Song Hu,Xiaoping Li,Fei Li,Yuqiang Liu,Hanjun Wei
Polymer derived SiCN ceramics (PDC SiCN) are the key high-temperature matrix materials for structural and stealth integrated ceramic matrix composites (CMC). However, low crystallization degree and homogeneous microstructure of PDC SiCN ceramics results in the lack of effective microwave attenuation mechanism. Hence, a new kind of nonmagnetic metal oxide (Y 2 O 3 ) was in-situ formed in SiCN ceramics to enhance the conductivity loss as well as the polarization loss. Y 2 O 3 modified PDC SiCN ceramics (SiCN-Y 2 O 3 ceramics) were fabricated by pyrolysis polysilazane with different Y(NO 3 ) 3 content at 900 ºC. For the SiCN-Y 2 O 3 ceramic, Y 2 O 3 nanoparticles were dispersed in SiCN ceramic uniformly forming a large number of Y 2 O 3 -SiCN heterogeneous amorphous interface, defects and dipole polarization to enhance its microwave absorbing properties. Due to the multiple polarization loss mechanism, SiCN-Y 2 O 3 ceramic with 10 wt% Y(NO 3 ) 3 content achieved excellent microwave absorption performance at a wide thickness range with the microwave absorbing efficiency more than 90% in the whole X band, and the RC min could reach − 50.2 dB at the thickness of 3.5 mm.
研究领域:
材料科学
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电磁学
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS
·
2025
·
IF 4.6
Houzhen Chen,Fuming Deng,Xiaotian Xing,Miao Gu,Jing Duo,Zhenhai Guo,Zhangjie Ye,Wenli Deng,Ziyi Liu,Qiang Chen,Yefei Zhang,Lei Zhang
In order to minimize the influence of metallic Co on the structural properties of polycrystalline diamond compact (PDC), this study employed an efficient electrolytic Co removal process to investigate the mechanism of complexing agents—Glycine (Gly), Citric Acid (CA), Tartaric Acid (TA), and Ethylene Diamine Tetraacetic Acid (EDTA)—in the electrolytic Co removal from PDC. The results show that Gly performed significantly better than CA, TA, and EDTA in Co removal from PDC. At the Gly concentration of 0.08 mol/L, the Co removal depth and Co removal rate reached 635 μm and 90.77 %, respectively, after 4 h of electrolysis. This significantly improves the efficiency of Co removal and enhances the abrasion ratio of PDC. Furthermore, Gly effectively relieved internal stresses within PDC and formed interconnected pore structures between diamond particles. These changes reduced the risk of delamination and cracking caused by residual stresses, thereby enhancing the service reliability of the material.
研究领域:
材料科学
·
电化学
·
表面工程
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS
·
2020
·
IF 3.407
Zhaoran Chen,Dejiang Ma,Shanmin Wang,Wenhao Dai,Pinwen Zhu,Yiqing Zhu,Baochang Liu
Ti-coated diamond with different particle sizes and proper amounts of cubic boron nitride (cBN) was used to fabricate polycrystalline diamond composite (PDC) with improved wear resistance and thermal stability under high temperature and high pressure (5.5–6.5GPa, 1500–1650 °C). The ratio of Ti-coated diamond powder, cBN powder and normal diamond powder was W 30 – 50 : W 4 – 8 : W 0 – 1 = 70: 15: 15. Cobalt (Co) was used as a binder, and cemented tungsten carbide was used as a substrate to sinter a new high-performance PDC. Ti and TiC on the surface of Ti-coated diamond reacted with cBN under high temperature and high pressure to generate new ceramic phases such as TiB 2 , TiN and TiN 0.3 , which have high hardness and good wear resistance. Compared with the conventional PDC, the impact toughness and wear resistance of PDC with Ti-coated diamond and cBN addition were enhanced by 19% and 28%, respectively. The ceramic phase acts as a protective barrier, which enhances the initial graphitization and oxidizing temperature to 942–950 °C, which were 162–170 °C higher than the conventional PDC. The new ceramic barrier wrapped around the surface of the diamond and Co after the formation of the D-D (diamond-diamond) bonding will give priority to the oxidation reaction of Co and diamond with oxygen, which prohibits cobalt-catalytic graphitization of diamond, meeting the needs of PDC thermal stability and wear resistance in the field of drilling.
研究领域:
材料科学
·
地质工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2026
·
IF 6
Ruichao Chen,Dingkang Peng,Bin Peng
SiAlCN thin films have great potential for high-temperature sensor applications due to their favorable thermal stability. In this work, to improve the high-temperature stability of SiAlCN thin films, a PDC-SiAlCN protective film for SiAlCN sensitive films was developed. The PDC-SiAlCN coating with a thickness of approximately 12 μm was successfully deposited on sputtered SiAlCN sensitive films via screen printing. SiAlCN thin films without a protective layer and those with Al 2 O 3 protective films were also prepared for comparison. The experimental results show that the SiAlCN films with PDC-SiAlCN coatings remain structurally intact after high-temperature testing, while the samples with Al 2 O 3 protective films show cracks as the temperature rises to 800 °C. The SiAlCN film samples with PDC-SiAlCN coatings exhibit a low resistance drift rate of about 0.71 %/h at 900 °C for 10 h. The drift rate of these samples is lower than that of the uncoated samples across the entire temperature range during isothermal tests. The samples with PDC-SiAlCN coatings not only deliver superior high-temperature stability within 800 °C, but also extend the applicable temperature limit up to 900 °C. During cyclic temperature tests from 200 °C to 900 °C, temperature data acquired from the SiAlCN film thermistor agree well with readings obtained from a commercial K-type thermocouple. The results reveal a low average measurement error of only 0.9 %. In terms of response time, the thermistors with a PDC-SiAlCN coating also exhibit obviously faster responses compared with the commercial thermocouple. The SiAlCN film thermistors with PDC-SiAlCN coatings are expected to be promising candidates for high-temperature monitoring applications.
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DOI
高影响因子
CERAMICS INTERNATIONAL
·
2026
·
IF 6
Ao Li,Renkai Chang,Zhidong Zhang,Jie Tang,Qipeng Liu,Bing Liu,Mengdong Ma,Qisong Li,Xiaozhe Cheng,Xiaoyan Guan,Qian Zhang,Yunchao Mu,Quan Huang
Silicon carbide (SiC) is a key structural ceramic renowned for its excellent comprehensive properties. However, its inherent brittleness often limits its service lifetime and reliability in high-wear applications. To address this issue, the present work combined the polymer-derived ceramic (PDC) route with spark plasma sintering (SPS), aiming to achieve additive-free densification of SiC-WC composites. Composite powders were prepared from liquid polycarbosilane (PCS) and nano-sized WC, and the resulting ceramics were systematically characterized. With increasing WC content, the composites exhibited synergistic improvements in hardness, fracture toughness, and tribological properties. The sample containing 50 wt% WC (SW-50) achieved a balanced set of properties, including a Vickers hardness of 22.7 ± 0.81 GPa, a fracture toughness of 6.0 ± 0.26 MPa m 1/2 , and a wear rate of 8.5 × 10 −7 mm 3 N −1 m −1 . These values represented improvements of approximately 11%, 46%, and 78%, respectively, relative to the WC-free sample (SW-0). All these findings demonstrates that the PDC-SPS process holds promising for achieving synergistic improvements in composite ceramics via microstructural regulation. This work provides a new and practical strategy for fabricating high-performance SiC-WC composites without sintering additives.
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DOI
高影响因子
危险品化学品经营许可证（带存储）