CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Xinyi Wan,Ting Wan,Chaochao Cao,Chengchun Tang,Yanming Xue,Youguo Yan,Zhen Li,Zhizhen Ye,Xinsheng Peng
The development of highly effective and durable CO 2 separation membrane is still a challenge for the carbon capture and storage. Herein, a novel BN nanosheets supported magnetic ionic liquid membrane (BN-SMILM) is constructed by nanoconfining magnetic ionic liquid (MIL) [P 6,6,6,14 ][FeCl 4 ] to the two-dimentional (2D) nanochannels of laminated BN membrane. The 2D nanochannels provide a well support and restricted space for the MIL. The nanoconfinement effect makes the magnetic [FeCl 4 ] - anions align along the center of 2D BN nanochannels, leading to selectively accelerate the CO 2 transport. The nanoconfinement effect and CO 2 separation mechanism are further explicated by the molecular dynamic simulations. As a result, compared with the polymer supported MIL membrane, the as-prepared BN-SMILM exhibits better CO 2 separation performance, with CO 2 permeability of about 227 Barrer and CO 2 /N 2 selectivity of 90 that is above the 2008 Robeson upper-bound. The BN-SMILM also presents excellent long-term stability after 7 days operation, revealing the promising applications in CO 2 separation. This work provides a new strategy to prepare high-performance supported liquid membrane materials towards practical environmental and energy application.
研究领域:
材料科学
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环境科学
·
能源科学
✓ 已验证
DOI
高影响因子
COMPOSITES PART B-ENGINEERING
·
2024
·
IF 12.7
Yu Zhang,Xu Shen,Qin Ma,Shuang Mu,Shaoming Dong,Jinshan Yang
In this work, the mechanical behavior of NITE-SiC f /SiC composites, accompanied by the damage mechanisms of SiC fibers and BN interphase during NITE process, are investigated. The results show that the fracture characteristic of NITE-SiC f /SiC composite is transformed from quasi-ductile mode to brittle mode with the elevating temperature, as well as severe damage of SiC fiber and BN interphase. The damage of SiC fibers is originated from high temperature, sintering aids corrosion and matrix compression. High temperature and sintering aids diffusion lead to the grain growth and strength degradation of SiC fibers. The damage of BN interphase is caused by the sintering aids corrosion, mainly the reaction of Al 2 O 3 , and matrix compression. The stress distribution is simulated via finite element analysis proving that up to 17.5 GPa and 17.0 GPa stress originated from matrix shrinkage during sintering process is applied to the fiber and interphase respectively, making the fiber deformation and interphase fragmentation. The degraded fiber strength and destroyed interphase structure weaken the load-bearing capacity and crack deflection ability, causing degradation of mechanical properties and reliability of composites. This work helps to comprehensively understand and optimize the properties of SiC f /SiC composites prepared by NITE process.
研究领域:
材料科学
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工程学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2021
·
IF 5.316
Xiangqian Jiang,Chuncheng Ban,Ling Li,Han Li,Jiandong Hao,Weiping Chen,Xiaowei Liu
The Seebeck coefficient, electrical conductivity and thermal conductivity of thermoelectric materials are related but not independent, so it is difficult to improve the figure of merit value of thermoelectric materials. In the compound with nanometer grain size, a large number of surface interfaces and various defects in the material will increase the phonon scattering, resulting in the decrease of lattice thermal conductivity. Therefore, the nano-structure of the material is expected to increase its thermoelectric performance parameters. This work presents is based on the self-synthesized BN nano-materials, different structure of the thermoelectric cell composed of nanomaterial BN and thermoelectric material bismuth telluride are designed and analyzed, and its output voltage and power are simulated. Low dimensional BN nanomaterials with low thermal conductivity may contribute to reduce the overall thermal conductivity of the battery and improve the output efficiency. The thermoelectric coefficient of the thermoelectric battery is approximately calculated to be 1.22, which will satisfy the power supply requirements of some small power electronic equipment in practical application.
研究领域:
材料科学
·
能源技术
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Shuangxi Lin,Longchen Gong,Ning Zhao,Huibo Zhao,Feigang Zhao,Yang Bai,Zhenhua Li,Wen Liu
Modulating metal-support interactions is critical for improving catalytic activity and product selectivity for CO 2 hydrogenation. Such modulation can be achieved by modifying the metal nanoparticles as well as the supports. Here, we prepared a novel catalyst, in which Ni nanoparticles were dispersed on CeO 2 and hexagonal boron nitride (h-BN) hybrid supports. The introduction of h-BN to Ni/CeO 2 -BN effectively improves the dispersion of Ni nanoparticles. More importantly, the abundant Ni-CeO 2 interfacial sites with enriched oxygen vacancies are formed over h-BN edge sites. The dispersed Ni species are anchored on CeO 2 via a unique interfacial structure, with electron-rich Ni (Ni δ− ) species. At the interfacial sites on Ni/CeO 2 -BN, the synergy between oxygen vacancies and Ni δ− , which enhances CO 2 activation and H 2 dissociation, respectively, renders superior catalytic performance for CO 2 methanation. In situ DRIFTS suggests formate as key rate-limiting intermediates on Ni-CeO 2 sites, while the formation of B-H bonds further promotes hydrogen activation and subsequently the catalytic performance. The modulation of metal-support interactions by spatial confinement effect by BN offers a new paradigm for designing metal/oxide catalysts for chemical transformations that requires bifunctionality as CO 2 hydrogenation.
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Nanomaterials
·
2019
·Vol. 9
·期 7
·1051
·
IF 4.034
Xiu Wang,Zhihuai Yu,Liang Jiao,Huiyang Bian,Weisheng Yang,Weibing Wu,Huining Xiao,Hongqi Dai
Hexagonal boron nitride (h-BN)-based heat-spreading materials have drawn considerable attention in electronic diaphragm and packaging fields because of their high thermal conductivity and desired electrical insulation properties. However, the traditional approach to fabricate thermally conductive composites usually suffers from low thermal conductivity, and cannot meet the requirement of thermal management. In this work, novel h-BN/cellulose-nano fiber (CNF) composite films with excellent thermal conductivity in through plane and electrical insulation properties are fabricated via an innovative process, i.e., the perfusion of h-BN into porous three dimensional (3D) CNF aerogel skeleton to form the h-BN thermally conductive pathways by filling the CNF aerogel voids. When at an h-BN loading of 9.51 vol %, the thermal conductivity of h-BN/CNF aerogel perfusion composite film is 1.488 W·m−1·K−1at through plane, an increase by 260.3%. The volume resistivity is 3.83 × 1014Ω·cm, superior to that of synthetic polymer materials (about 109~1013Ω·cm). Therefore, the resulting h-BN/CNF film is very promising to replace the traditional synthetic polymer materials for a broad spectrum of applications, including the field of electronics.Keywords:CNF aerogel;perfusion;h-BN;thermal conductivity;electrical insulation
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
HIGH PERFORMANCE POLYMERS
·
2017
·
IF 1.179
Jun Song,Zhendong Dai,Jingyu Li,Haichao Zhao,Liping Wang
Boron nitride-hydroxyl (BN–OH) was synthesized with silane coupling agent (KH550) in order to achieve epoxy/BN nanocomposites with excellent thermal, tribological, and mechanical properties. This is an efficient method to improve epoxy nanocomposite properties. These properties were investigated by friction and wear test, thermogravimetric analysis, and dynamic mechanical analysis. The wear mechanisms were studied by scanning electron microscopy. Surface modification of BN–OH with silane coupling agent significantly enhanced its thermal stability. Storage modulus of the nanocomposite with 2% epoxy/BN increased by nearly 300% in comparison with that of pure epoxy. The results exhibit outstanding performance of the epoxy/BN nanocomposites compared with pure epoxy resin.
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
CONSTRUCTION AND BUILDING MATERIALS
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2021
·
IF 6.141
Yuan Fang,Aoxuan Wang,Keze He,Hongying Pan,Jiajun Liao,Zhu Ding,Feng Xing,Huirong Le,Xianfeng Wang
This article investigates the key interface properties of geopolymers reinforced by SiC whiskers loaded with BN coating (BN/SiCw) and the insight of mechanical performance and microstructures of the resulting composites. The interesting diverse strength evolutions of geopolymer composites calcinated at various temperatures suggest a result of rivalries of multiple factors including BN coating, geopolymer matrix transformations, SiC whiskers. A positive effect on whisker pull-out phenomenon has been achieved via the chemical bonding between SiC whisker (SiCw) and BN coating and the rough physical interface between BN coating and geopolymers; the addition of SiCw and BN/SiCw promotes the polycondensation reaction of geopolymers and the addition of the latter is superior. Through changing the pore structure characteristics of the composites, the SiCw in composites can release their excessive vapor pressure in the closed pores which is the main reason attributing to the strength loss of geopolymers at 900 °C. In addition, BN coating can make up for the mismatch of thermal expansion coefficient between SiCw and geopolymers, increasing the strength of the composites by 30.9% at 900 °C, whereas whisker pull-out and crack deflection are the main toughening effect for BN/SiCw.
研究领域:
材料科学
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工程学
✓ 已验证
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
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2022
·
IF 6.364
Shile Chen,Liang Wang,Gang He,Gang Shao,Hailong Wang,Jiangtao Li,Chang-An Wang
Nitride based ceramics are considered as a kind of promising material for structural and functional integration due to their robust structure, extreme environmental resistance and electromagnetically transparency. It is still challenging to prepare nitride based ceramics with homogeneous and controllable microstructure because of their low self-diffusion coefficient and difficulty in sintering. Here, we developed a gelcasting-SHS process by combining gelcasting forming and self-propagating high temperature synthesis (SHS) for the preparation of porous BN-Si 3 N 4 composite ceramics. First, carbon residue problem in the gelcasting -SHS process was studied. Based on the result, porous BN-Si 3 N 4 composite ceramics with high porosity (69.42 ~ 86.48%), high strength (21.7 ~ 81.0 MPa) and low dielectric constants (1.42 ~ 2.87) were synthesized. In addition, the thermal shock resistance of porous BN-Si 3 N 4 composite ceramics until 1000 ℃ was evaluated.
研究领域:
材料科学
·
陶瓷工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Advanced Ceramics
·
2021
·Vol. 10
·期 6
·1317-1325
·
IF 6.707
Liu Zetan,Zhao Shiqiang,Yang Tian,Zhou Ji
It is possible to improve the machinability of aluminum nitride-hexagonal boron nitride (AlN-h-BN) ceramics while maintaining high strength and high thermal conductivity. The composite ceramics with 0–30 wt% BN as secondary phase were prepared by hot pressed sintering, using yttrium oxide (Y 2 O 3 ) as sintering aid. The phase composition, density, microstructure, mechanical properties, thermal conductivity, and dielectric properties were investigated. The sintering additives were favorable to purify the grain boundaries and improve densification, reacting with oxide impurities on the surface of raw material powder particles. The optimum BN content improved the flexural strength and fracture toughness of composite ceramics with 475 MPa and 4.86 MPa·m 1/2 , respectively. With increasing the amount of BN, the thermal conductivity and hardness of composites gradually decreased, but the minimum value of thermal conductivity was still 85.6 W·m −1 ·K −1 . The relative dielectric constant and dielectric loss tangent of the samples ranged from 6.8 to 8.3 and from 2.4 × 10 −3 to 6.4 × 10 −3 , respectively, in 22–26 GHz.
研究领域:
材料科学
·
工程学
✓ 已验证
产品关联
DOI
高影响因子
Scientific Reports
·
2019
·Vol. 9
·期 1
·1-11
·
IF 4.011
Chen Yang,Wang Xing,Yu Chao,Ding Jun,Deng Chengji,Zhu Hongxi
r-BN nanoflakes were synthesized using KBH 4 and NH 4 Cl as the main raw material in a high-purity nitrogen atmosphere. The effects of salt and salt-free conditions and heating temperature on the synthesis of BN were studied. The molten-salt method was used to synthesize BN at 650 °C, which was 250 °C lower than the BN synthesis method without salt. Furthermore, at 1000 °C the prepared flake-like BN crystals showed good crystallinity, uniform morphology, a particle diameter of 200–300 nm, and a thickness of 40–70 nm. Moreover, the specific surface area of BN was 294.26 m 2 /g. In addition, the BN synthesized at 1100 °C had a large elastic modulus value and good oxidation resistance.
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
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Sheng Li,Sidra Subhan,Liqin Zhou,Jing Li,Zhongxing Zhao,Zhenxia Zhao
Improving the adsorption capacity of the volatile organic compounds (VOCs) will inevitably decrease the desorption efficiency and hence increase more energy-consumption, which has become a crucial challenging problem for MOFs modification and composition toward VOCs adsorption. Herein, a thermal-conductive composition strategy was proposed to anchor BN nanosheets (BNNS) into HKUST-1 crystals via “N/O-Cu-O” interface. The formed HKUST-1@BNNS composite maintained high surface area (1633.7 m 2 /g having more microporous) and enhanced heat diffusivity (1.8 times of HKUST-1), simultaneously. This enabled significant increase of toluene adsorption capacity on HKUST-1@BNNS up to 4.3 mmol/g (2.8 times of HKUST-1) at ultra-low pressure ( P / P 0 ≈ 0.001) and higher desorption rate of toluene ( k ds = 29.3 × 10 −2 , 4.0 times of HKUST-1) with lower desorption activation energy ( E d = 33.5 kJ/mol). Compared with many other state-of-the-art adsorbents (e.g., MOFs, zeolites and activated carbons), it has a much higher adsorption capacity and regeneration rate. Thus, thermal-conductive MOFs construction can be deemed as smart strategy to enhance adsorption efficiency and save desorption energy for VOCs capture.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ELECTRONIC MATERIALS
·
2024
·
IF 2.2
Tu Xuesong,Zhou Hong,Chi Hao,Zhou Jian
Massive heat generated by electronic components during continuous operation will affect the operation of the equipment, so it is of significance to face up to the heat dissipation problem of electronic packaging materials. Epoxy resin (EP) is widely applied to electronic components for its excellent electrical insulation and processability. To improve the thermal conductivity of composites, this study prepared BN-Al 2 O 3 /EP composites by adding a hybrid of modified boron nitride (mBN) and modified alumina (Al 2 O 3 ) into EP. Profiting from the high thermal conductivity and low dielectric constant of BN and Al 2 O 3 , the thermal and dielectric properties of EP composites were improved. Specifically, the composite of 4 wt.% BN-3 wt.% Al 2 O 3 not only occupied the high thermal conductivity 0.25 W/(m K) at 50°C, but also kept the relatively inferior dielectric constant (4.27) and the low dielectric loss (0.0037) at 10 2 Hz. The composite could be applied in electronic packaging materials as it has excellent dielectric properties and high thermal conductivity.
研究领域:
材料科学
·
电子工程
·
复合材料
✓ 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）