Materials
·
2019
·Vol. 12
·期 3
·390
·
IF 2.972
Zhiying Hu,Dingheng Zheng,Rong Tu,Meijun Yang,Qizhong Li,Mingxu Han,Song Zhang,Lianmeng Zhang,Takashi Goto
Highly-oriented polycrystal 3C-SiC bulks were ultra-fast fabricated via halide chemical vapor deposition (CVD) using tetrachlorosilane (SiCl4) and methane (CH4) as precursors. The effects of deposition temperature (Tdep) and total pressure (Ptot) on the orientation and surficial morphology were investigated. The results showed that the growth orientation of 3C-SiC columnar grains was strongly influenced byTdep. With increasingTdep, the columnar grains transformed from <111>- to <110>-oriented. The arrangement of <111>-oriented columnar grains was controlled byPtot. Lotus-, turtle-, thorn-, and strawberry-like surface morphologies were naturally contributed by different arrangements of <111>-oriented grains, and the deposition mechanism was discussed. The wetting behaviors of CVD-SiC samples by molten aluminum were also examined at 1173 K in a high vacuum atmosphere.Keywords:3C-SiC;chemical vapor deposition (CVD);orientation;surficial morphology;wettability
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Wenxuan Yang,Wei Huang,Cuicui Li,Chongjie Wang,Chitengfei Zhang,Rong Tu,Song Zhang
Highly <111>-oriented 3C-SiC coatings were fabricated by chemical vapor deposition method at different temperatures. As deposition temperature increased from 1473 K to 1773 K, the surface structure of <111>-oriented 3C-SiC transitioned from hexagonal structure with sixfold symmetry to hill-like structure, and finally to conical porous surface composed of stacked short rods. Owing to alteration of surface structure, the hardness of 3C-SiC coatings presented a trend of initially increasing and subsequently decreasing. The 3C-SiC coating deposited at 1673 K possessed the highest hardness, with a value of 42.08 GPa. The average friction coefficient for 3C-SiC/Si 3 N 4 pair ranged from 0.258 to 0.569. The wear rate and hardness exhibited opposite trends. Compared with 3C-SiC coatings prepared at the other three temperatures, the 3C-SiC coating deposited at 1573 K exhibited the lowest wear rate under loads of 5 N, 10 N, and 15 N. Furthermore, the lowest wear rate, recorded at 15 N, was 4.1 × 10 −6 mm 3 /Nm, attributed to high hardness and uniform grain size. The wear mechanism of <111>-oriented 3C-SiC coatings during dry sliding primarily involved fracture, leading to fatigue and third-body wear.
研究领域:
材料科学
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表面工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Wei Ding,Pengjian Lu,Qingfang Xu,Chitengfei Zhang,Rong Tu,Song Zhang
In the integrated circuit industry, heat is transferred through the contact between wafers and the chemical vapor deposited (CVD) 3C–SiC wafer susceptor . Understanding the out-plane thermal conductivity of CVD 3C–SiC is crucial in this context. The influence of grain size and grain boundary characteristics on out-plane thermal conductivity for <111>-oriented CVD 3C–SiC was discussed in this study. The out-plane thermal conductivity sharply decreases from 146.4 W/m⸱K to 122.3 W/m⸱K when the grain size approaches 11.04 μm. This paper suggests that the significant accumulation of dislocations at high-angle grain boundaries is the primary cause of this phenomenon. The substantial lattice strain impedes phonon transfer between grain boundaries, reducing overall phonon mobility. These findings suggest that manipulating the grain boundary angle is an effective means to fine-tune heat transfer in <111>-oriented CVD 3C–SiC.
研究领域:
材料科学
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热物理学
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2015
·Vol. 7
·期 19
·8955-8961
·
IF 7.394
Tao Yang,Xiwang Chang,Junhong Chen,Kuo-Chih Chou,Xinmei Hou
B-doped 3C-SiC nanowires have been synthesized via a facile and simple carbothermal reduction method at 1500 °C for 2 h in a flowing purified argon atmosphere. The obtained nanowires possess a single crystalline and finned microstructure with fins about 100–200 nm in diameter and 10–20 nm in thickness. The diameter of the inner core stem is about 80 nm on average. Due to the smaller band gap, the finned microstructure and the single crystalline nature, the B-doped 3C-SiC nanowires demonstrate efficient activity as high as 108.4 μmol h−1 g−1 for H2 production, which is about 20 times higher than that of 3C-SiC nanowhiskers and 2.6 times higher than the highest value reported in the literature for SiC materials.
研究领域:
材料科学
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能源科学
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光催化技术
✓ 已验证
DOI
高影响因子
APPLIED PHYSICS LETTERS
·
2024
·Vol. 124
·期 24
·
IF 3.5
Chen Wenkang,Wu Xiangshui,Deng Shichen,Yang Nuo,Xu Xiangfan
Strain provides an additional mechanism in tuning the thermal/electrical properties of nanostructures and therefore has triggered lots of interest in recent years. However, experimental research about the strain effect on the thermal conductivity of nanowires is still limited, especially in the low-temperature range, which is important in understanding the physics of strain-induced regulation in thermal conductivity. Here, we present thermal transport measurements of bent silicon carbide nanowires at temperatures ranging from 20 to 300 K. Reduction in thermal conductivity compared to their straight counterparts is observed. More specifically, the relative change is up to 55% at 20 K and descends with temperature, which is due to the inhomogeneous strain-induced phonon scattering. This study will deepen the understanding of thermal properties in nanostructures with strain.
CAS / MDL:
研究领域:
材料科学
·
热物理
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Zhuotao Song,Zhixiao Wang,Tao Yang,Yanglong Hou,Enhui Wang,Hongyang Wang,Kuo-Chih Chou,Xinmei Hou
Silicon carbide (SiC), recognized as a high-quality dielectric material, stands out as a promising candidate for wave-absorbing applications. Nevertheless, at room temperature, SiC often suffers from suboptimal impedance matching and loss coefficients, resulting in inferior wave-absorbing performance. In response to this challenge, we synthesized polymer-derived ceramics (PDCs)-SiC fibers rich in heterojunctions and turbostratic carbon. This was achieved by incorporating cobalt (Co) catalysts into the organopolysilazane spinning precursor, followed by high-temperature pyrolysis. We systematically investigated the influence of Co catalyst content and pyrolysis temperature on the electromagnetic absorption (EMA) properties of PDCs-SiC and elucidated the underlying wave-absorption mechanism. Our findings reveal that the introduction of an appropriate quantity of Co catalyst not only effectively reduces the temperature required for the conversion of organopolysilazanes into SiC but also facilitates the growth of 2H-SiC and a substantial amount of turbostratic carbon within the fibers. This unique structure serves to enhance the conductivity loss and simultaneously generates an abundance of interfaces and dipole polarization. The fabricated mesoporous 2H/3C-SiC heterojunction fibers exhibit outstanding wave-absorbing capabilities. Specifically, at a thickness of 1.4 mm, they achieve a minimum reflection loss (RL min ) of −53.93 dB, and at a thickness of 1.6 mm, they possess an effective absorption bandwidth (EAB) of 3.21 GHz. Moreover, the EAB can be precisely regulated by adjusting the Co content. This work offers innovative perspectives for the subsequent design of novel wave-absorbing materials with enhanced absorption capacity.
研究领域:
材料科学
·
电磁学
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产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2016
·Vol. 4
·期 27
·6466-6472
·
IF 5.066
Xiaoxiao Li,Shanliang Chen,Pengzhan Ying,Fengmei Gao,Qiao Liu,Minghui Shang,Weiyou Yang
Silicon carbide (SiC) is recognized as a promising substitute for the currently used Si for exploring robust pressure sensors with desired high sensitivities and excellent abilities to serve under harsh work conditions. In the present work, we reported the giant piezoresistance effect of p-type 3C-SiC nanowires with B dopants, which were synthesized by catalyst-assisted pyrolysis of polysilazane. The transverse electromechanical properties of SiC nanowires were investigated at loading forces applied using a conductive atomic force microscopy (C-AFM) tip. The resistances of the as-synthesized SiC nanowires exhibit an increase with the increase of compressed stresses at the same bias voltages, representing their negative piezoresistance behaviors. The measured negative piezoresistance coefficient π[10] of the nanowire fell in the range of −8.83 to −103.42 × 10−11 Pa−1 as the applied loading forces ranged from 51.7 to 181.0 nN. The giant gauge factor (GF) could be up to −620.5, which was enhanced by more than 10 times compared to the highest ever reported for SiC nanostructures.
研究领域:
材料科学
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纳米技术
·
传感器技术
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Xin Wang,Tao Yang,Xinmei Hou,Yapeng Zheng,Enhui Wang,Zhengtao Du,Sheng Cao,Hailong Wang
Silicon carbide nanowires (SiC NWs) were successfully synthesized using graphene and Si powder as raw materials in NaCl–NaF at 1300–1400 °C for 6 h. The synthesized SiC NWs have two crystal phases due to the presence of molten salt, which formed the 2H/3C–SiC heterojunction structure. The possible synthesis mechanism of SiC NWs is “dissolution-diffusion-reaction”. Besides, photoluminescence (PL) spectra of 2H/3C–SiC heterojunction NWs show that the main emission peak has a significant blue shift, locating in 350–600 nm. The main reason is caused by the defects of 2H/3C–SiC heterojunction structure and the spontaneous polarization of 2H–SiC nano segments.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Applied Ceramic Technology
·
2019
·Vol. 16
·期 3
·1004-1011
·
IF 1.074
Rong Tu,Xian Zhang,Youfeng Lai,Mingxu Han,Song Zhang,Ji Shi,Haiwen Li,Takashi Goto,Lianmeng Zhang
Cubic SiC (3C-SiC) is a promising material for nuclear industry applications due to its excellent properties. In this report, a highly oriented thick 3C-SiC coating with good crystallinity was prepared on the inner surface of a monolithic graphite tube via high-frequency induction-heated halide chemical vapor deposition using SiCl 4 , CH 4 , and H 2 as precursors. The texture coefficient ( T C (hkl) ), microstructure, and deposition rate along the tube axis was studied. 3C-SiC coating with a high (111) orientation and crystallinity was obtained. Along the tube axis, T C (111) was consistent with the temperature distribution. The surficial morphology of the 3C-SiC coating changed from pebble-like to hexangular facet and then to hemispherical. The deposition rate and coating thickness were 300 μm/h and 615 μm, respectively, which is sufficiently rapid and thick enough to obtain free-standing SiC tubes for nuclear reactors.
研究领域:
材料科学
·
核工程
·
薄膜沉积
·
陶瓷材料
·
化学气相沉积
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）