APPLIED SURFACE SCIENCE
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2021
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IF 6.707
Jianmei Pan,Yahai Zhang,Yi Guan,Yingnan Yan,Hua Tang,Xianglong Liu,Mengdi Wang,Xiangxin Wei
The development of hydrogen (H 2 ) production photocatalyst with low cost, non-precious metal and high-activity for commercial application is a long-term target and challenge. In this work, novel silicon carbide (SiC) nanofibers/graphitic carbon nitride (g-C 3 N 4 ) nanosheets (SiC/CNNS) decorated via multipurpose nickel (Ni) nanoparticles were prepared by an easy heat treatment followed by hydrothermal method. The tight Ni interface layers as cocatalyst and electron transfer mediator can significantly enhance the H 2 production property over SiC/CNNS nanoheterojunctions under light-emitting diode (LED) illumination. The optimal Ni/SiC/CNNS with a mass fraction of 10% Ni loading shows the most superior H 2 -generation rate of 6183 μmol g −1 h −1 , which is approximately 53, 3 and 227 times compared to CNNS, 10 %Ni/CNNS and SiC/CNNS, respectively. The metallic Ni nanoparticles play the leading and multifunctional roles in improving photocatalytic activity, including collecting the photo-generated electrons efficiently, transferring and separating the charge carriers rapidly, facilitating the H 2 -production kinetics and decreasing the overpotentials of surface reactions for H 2 -production. It is highly expected that the multipurpose and non-precious metal cocatalyst to form tight interface layers can supply a simple and universal strategy to design high-efficiency cocatalyst-semiconductor–semiconductor photocatalysts for H 2 production.
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高影响因子
APPLIED SURFACE SCIENCE
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2021
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IF 6.707
Wantang Wang,Baoguo Zhang,Yunhui Shi,Jiakai Zhou,Ru Wang,Nengyuan Zeng
Silicon carbide (SiC) is challenging to process by chemical mechanical polishing (CMP) given its anomaly mechanical hardness and chemically inert. However, improving the SiC-CMP performance including machining efficiency and surface quality is critical for developing power semiconductor devices with low cost, high efficiency, and high stability. Here, this research aims at combining mixed abrasive slurry (MAS) with photocatalytic effect in the SiC-CMP process, thus enabling an efficient enhanced CMP technology with low-cost and high-performance. Specifically, this paper describes the fabrication process of MAS through a high-energy ball milling method and discusses the polishing performance of the slurry with or without the presence of UV irradiation. By using MAS consisting of Al 2 O 3 and ZrO 2 abrasives, a material removal rate of 694 nm/h and surface roughness (Ra) of 0.489 nm can be obtained under UV irradiation. Additionally, the abrasive morphology, element composition, particle size distribution, Zeta potential, and its chemical effect of the MAS are also analyzed. In particular, a two-step strategy, namely the preparation of MAS and polishing with UV irradiation, is proposed to enhance the SiC-CMP efficiency, and an in-depth analysis of the improvement mechanism for each step is discussed.
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高影响因子
CERAMICS INTERNATIONAL
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2021
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IF 4.527
Zihe Li,Zixuan Chang,Xinran Liu,Weimin Zhao,Xu Zhang,Shikang Xiao,Yuhang Tian,Aijun Li,Guifang Han,Jianzhang Li,Jingde Zhang
High strength and thermal shock resistant mullite-bonded porous SiC ceramics are essential for applications in catalyst, hot gas/solid filtration/separation fields. However, these properties were limited by the contradictory issue: higher temperature is necessary for the formation and densification of mullite bond phase, while lower temperature is preferred to avoid sever oxidation of SiC accompanied with detrimental cristobalite phase. Herein, a novel composite additive system, Al(OH) 3 +Y 2 O 3 +CaF 2 , was proposed to solve this problem for one shot. Flexural strength as high as 113 MPa (40.3 vol% porosity) was achieved for samples sintered in air, even higher than that fabricated by expensive SPS technique (103 MPa, 35.7 vol%). Critical quenching temperature reached 547 °C, around 227 °C improved. Meanwhile, additives acted as pore formers and small variation of them could effectively modify the size and shape of pores. The evolution of pore structure with additives was thoroughly evaluated and models were established for the first time. Correlations of phase composition, microstructure, porosity, pore size and shape to the performance of porous SiC were investigated. This work provides a flexible strategy to simultaneously control the mechanical performance and pore structure for low cost porous SiC ceramics.
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高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2023
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IF 8.2
Xiangyu Chen,Jiahua Ma,Xiaoshuai Sun,Chuanshan Zhao,Jiehua Li,Hui Li
The rational design of porous carbon materials and hydrogel electrolytes with excellent mechanical properties and low-temperature tolerance are significance for the development of flexible solid-state supercapacitors. In this study, we introduce a novel methodology for synthesizing SiC/N, S-doped porous carbon nanosheets from bamboo pulp red liquor (RL). We leverage the SiO 2 and the sodium salt in RL as templates and sodium lignosulfonate as sulfur dopants for the pyrolysis process and use NH 4 Cl as a nitrogen dopant. This innovative approach results in a material with a remarkable specific surface area of 1659.19 m 2 g −1 , a specific capacitance of 308 F g −1 at a current density of 1 A g −1 and excellent stability. Additionally, we harness alkali lignin extracted from RL to enhance a poly (vinyl alcohol) (PVA) matrix, creating a gel electrolyte with low-temperature tolerance and outstanding mechanical properties. A flexible solid-state supercapacitor, which incorporates our electrodes and gel electrolyte, demonstrates high energy density (5.2 W h kg −1 at 251 W kg −1 power density). Impressively, it maintains 82 % of its capacitance over 10,000 cycles of charge and discharge. This provides a new solution for the development of flexible solid-state supercapacitors.
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PubMed
高影响因子
COMPOSITES PART B-ENGINEERING
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2026
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IF 14
Zhiyu Yang,Feiyan Cai,Dewei Ni,Bowen Chen,Hongda Wang,Yan Gu,Meng Liu,Yusheng Ding,Shaoming Dong
Ultra-high temperature ceramic matrix composites (UHTCMCs) are essential for thermal protection in extreme aerospace environments. The role of ultra-high temperature ceramic (UHTC) matrix architecture in governing thermal transport and ablation resistance remains insufficiently understood. In this work, high-thermal-conductivity C f /HfC-SiC composites with distinct matrix structures were fabricated via slurry infiltration (SI) and precursor infiltration and pyrolysis (PIP). The PIP route, enabled by molecular-scale precursor infiltration, yields a uniform HfC dispersion within the SiC matrix, establishing a continuous phonon transport network that delivers an axial thermal conductivity as high as 296 W/(m·K). In contrast, the SI route leads to localized HfC enrichment in inter-bundle pores, which, upon ablation, oxidizes into abundant HfO 2 particles that pin the SiO 2 melt, producing a dense and erosion-resistant oxide scale. Consequently, the SI-HfC composite exhibits a linear ablation rate of 0.042 μm/s and a mass ablation rate of 3.61 mg/s, with only a 9.31% degradation in axial thermal conductivity after 100 s ablation at 4.5 MW/m 2 , suffers less thermal conductivity degradation than the PIP-HfC (11.80%). This work elucidates the processing-microstructure-property correlations in UHTCMCs, providing a quantitative basis for route selection in high-thermal-conductivity thermal protection systems.
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高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
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2023
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IF 3.9
Wen Yan,Zhe Chen,Guangqiang Li,Shaosong Hong,Nan Li
In present work, the novel Al 2 O 3 -C ceramic filter fabricated by using microporous corundum-spinel powder instead of dense Al 2 O 3 powder and reinforced by SiC whiskers is proposed. The effects of Si powder content (0, 3, 6, and 9 wt. %) on the microstructures and mechanical properties of the filters were studied. After replacing the α-Al 2 O 3 micro-powder with microporous corundum-spinel powder, the in situ spinel whiskers were formed inside the filter skeleton under the reducing atmosphere. The rough surface structure of the microporous powder increased the interface contact area with the small-sized carbon particles, resulting in a compact interface bonding in the filter skeleton and a higher cold compressive strength of the filter. When the Si powder content increased to 6–9 wt. %, the in-situ SiC whiskers were formed not only between the microporous powder, but also inside the pores near the surface of it by vapor-solid reaction mechanism in the filter skeleton. The SiC whiskers synergized with the microporous powder to form a more compact interface structure, thus remarkably enhancing their cold compressive strength and thermal shock resistance. Overall, the mechanical properties of the filters were significantly improved by the addition of 9 wt. % Si powder. The filter skeleton had an apparent porosity of 36.2% and a bulk density of 1.93 g/cm 3 . The filter also exhibited a high cold compressive strength of 1.59 MPa and a superior thermal shock resistance. It has the potential for better purification efficiency on molten steel in the future due to a rougher skeleton surface structure compared to existing Al 2 O 3 -C filters.
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高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
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2023
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IF 5.7
Liang Zhou,Jianbao Hu,Yunhui Zhang,Min Tan,Chunjing Liao,Han Luo,Yanmei Kan,Xiangyu Zhang,Jinshan Yang,Xiaowu Chen,Shaoming Dong
The phase transition of thermally grown oxide (TGO) has been proven to be an important factor affecting the durability of EBCs. Yb 2 O 3 and Yb 2 SiO 5 can react with silica to form silicate, which can reduce the TGO thickness and extend the lifetime of EBCs. In this paper, the Yb 2 SiO 5 -Yb 2 O 3 -Si-SiC ceramic was prepared by tape casting combined with silicon reactive melt infiltration. The oxidation properties of the ceramic were evaluated at 1200–1400 °C. With the increase in temperature, the content of SiO 2 in the oxide layer decreased and the content of Yb 2 Si 2 O 7 increased. A dense and continuous Yb 2 Si 2 O 7 layer was formed at 1400 °C. Yb 2 Si 2 O 7 is formed at the edge of Yb 2 SiO 5 , then Yb 3+ diffuses outwards, Si 4+ diffuses inwards and gradually forms Yb 2 Si 2 O 7 from the outside to the inside.
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高影响因子
POLYMER COMPOSITES
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2023
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IF 5.2
Xintong Zhao,Wei Wu,Dietmar Drummer,Yi Wang,Chao Liu,Shuo Li,Zijian Lu
The chemical reduction method is a simple and popular way to contrast the graphene network to improve the polymer matrix's thermal conductivity. And hybrid thermal conductive fillers composed of two or more mixed fillers through chemical synthesis usually have better thermal conductivity because of the synergistic effort. In this work, silicon carbide nanowires (SiC NWs) in graphene aerogels are synthesized with the chemical vapor deposition method, acting as bridges for phonon transmission between adjacent graphene sheets. The RGO/SiC NWs aerogel-endowed EP composites have a high thermal conductivity of 3.79 W/mK at a filler loading of 5.5 wt%, and 4.23 W/mK at a filler loading of 7.5 wt%, which is 1895% and 2126% higher than pure EP resin, respectively. Finite element analysis (FEA) is utilized to analyze the heat conduction mechanism of composites at last.
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高影响因子
CHEMICAL ENGINEERING JOURNAL
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2021
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IF 13.273
Boyu Li,Yingjie Li,Yehui Dou,Yuzhuo Wang,Jianli Zhao,Tao Wang
To achieve high heat storage capacity, excellent mechanical, optical and thermal properties in calcium looping thermochemical heat storage, the novel SiC/Mn co-doped CaO pellets were fabricated by the extrusion-spheronization method. The heat storage performances of the novel CaO pellets were studied under harsh calcination (pure CO 2 , 950 °C) and pressurized carbonation (pure CO 2 , 13 bar, 800 °C) conditions in a dual fixed-bed reactor system. The additions of SiC and Mn enhance the cyclic stability of CaO pellets during the multiple heat storage cycles. When the mass ratio of CaO:SiC:MnO 2 is 100:5:5, the co-doped CaO pellets exhibit an excellent heat storage performance. The effective conversion and heat storage density of the co-doped CaO pellets are 41.5% higher than those of original CaO pellets, respectively. Meanwhile, the co-doped CaO pellets possess a good optical absorption capacity and a high thermal conductivity , which are 17.6 and 3.2 times as high as those of original CaO pellets, respectively. In addition, the co-doped CaO pellets show much higher crushing strength and lower weight loss during the attrition test. The stronger interaction between SiC and CaO cluster mitigates the movement of CaO, which is determined by density functional theory simulation. The adsorption of CO 2 onto the CaO surface is enhanced by the addition of Mn. Therefore, SiC/Mn co-doped CaO pellets used in the calcium looping thermochemical heat storage process appear promising.
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高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
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2020
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IF 4.495
Youlin Jiang,Dewei Ni,Bowen Chen,Jun Lu,Feiyan Cai,Xuegang Zou,Chunjing Liao,Hongda Wang,Shaoming Dong
In this work, 3D-C f /HfC-SiC-based composites were fabricated and optimized via reactive melt infiltration (RMI) of Si into porous C f /HfC-C preforms prepared by a sol-gel processing. The physical and chemical processes involved during the fabrication were identified and analyzed in details. It is revealed that fibers and interphase of the composites can be eroded during carbothermal reduction process, which can be further aggravated during RMI, with the formation of Hf-containing substance on the fibers surface. The fibers and interphase degradation is mainly induced by the reactions between HfO 2 and C/SiC interphase layers at elevated temperatures. Accordingly, a two-step carbothermal reduction treatment was proposed for the optimization of the fabrication procedure. As a result, less fiber/interphase erosion and improved mechanical properties are achieved in the composites, with the bending strength increased by ∼49 % (from 214.1 ± 15.7 MPa to 319.0 ± 26.0 MPa).
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高影响因子
CHEMICAL ENGINEERING JOURNAL
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2020
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IF 10.652
Yunpu Wang,Linyao Ke,Yujie Peng,Qi Yang,Yuhuan Liu,Qiuhao Wu,Yujie Tang,Haibin Zhu,Leilei Dai,Zihong Zeng,Lin Jiang,Roger Ruan
In view of the poor selectivity of aromatic hydrocarbons in bio-oil from biomass pyrolysis and the high pressure drop and rapid coking and deactivation of catalyst in industrial scale, a microwave-driven HZSM-5@SiC ceramic foam has been constructed, and applied to the ex-situ catalytic fast pyrolysis of soapstock to improve the content of aromatic hydrocarbons in bio-oil. The effects of different catalysts and heating modes and mass ratios of HZSM-5@SiC ceramic foam to soapstock on the distribution of pyrolysis products have been investigated. In addition, combined with the comparison of microwave and electric heating, the deactivation characteristics of HZSM-5@SiC ceramic foam have been studied. Finally, the process of preparing aromatic oil by microwave-driven catalytic pyrolysis of soapstock was discussed. Experimental results indicate that compared with HZSM-5, HZSM-5@SiC ceramic foam has a higher yield of bio-oil and higher aromatization activity. Under microwave heating, the relative content of aromatic hydrocarbons increases from 25.18% to 100% when the mass ratio of HZSM-5@SiC ceramic foam to soapstock increases from 0:1 to 1:1. Compared with electric heating catalysis, HZSM-5@SiC ceramic foam has the lowest yield of coke under microwave heating. After five consecutive uses, it still maintains more than 90% catalytic activity and has higher stability, which provides a scientific basis for the pilot scale experiments of soapstock catalytic pyrolysis.
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高影响因子
POWDER METALLURGY
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2020
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IF 1.793
Dongxue Liu,Qiqi Zhang,Longchao Zhuo,Yiheng Zhang,Yanlin Wang,Jintao Xu
In this paper, a combined processing method of mechanical alloying and infiltration was used to prepare the WCu-x wt-%SiC (x = 0.5, 1, 2, 3) composites. The microstructure, density, electrical conductivity and compressive behaviour of the composites were studied comparatively. First a decreasing and then an increasing particle growth trend was obtained, indicating that a small content of SiC below 1 wt-% was beneficial for particle refinement. Besides this, with the increase of the SiC content, both the density and electrical conductivity decreased gradually. Consistent with the particle–particle contiguity of the highest value of 0.404, the WCu-1 wt-%SiC composite showed the best compressive properties. Further electron backscattering diffraction results revealed that the ultrafine-grained SiC particles, which are distributed homogeneously in the composite with lower Schmid factor values would perturb the dislocation motion to make proliferation of more dislocations, exhibiting unordinary strain-hardening during deformation.
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高影响因子
危险品化学品经营许可证（带存储）