JOURNAL OF MATERIALS SCIENCE
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2022
·Vol. 57
·期 42
·19799-19816
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IF 4.682
Zhu Jishi,Li Xinshuo,Yang Rui,Wen Jin,Li Xiaoke
The widespread application of solar-thermal absorbers is currently hindered by their low absorption efficiency and high capital cost. Therefore, many initiatives, including direct absorption solar collectors (DASCs), are currently under way to improve the efficiency of the absorbers. In this regard, the application of TiN-modified h-BN nanosheets in DASCs is studied in this paper. Their superior solar absorptivity and thermal conductivity are based on the plasma plasmon effect of nanoparticles and the high thermal conductivity of h-BN nanosheets, respectively. In the experiment, five different concentrations (20, 40, 60, 80, 100 ppm) of TiN@h-BN composite nanofluids were prepared by a two-step method. The stability and optical properties of the nanofluids were analyzed. In addition, thermal loss and exergic efficiency of photothermal conversion system were analyzed and discussed. Combined with localized surface plasmon resonance (LSPR) of TiN nanoparticles and h-BN light reflection properties, the photothermal conversion of TiN@h-BN composite nanofluids was improved in DASCs. The 80 ppm nanofluid showed the best exergic efficiency, with an average exergic efficiency of 83%. Meanwhile, the photothermal conversion efficiency of 80 ppm TiN@h-BN composite nanofluid reaches the maximum 78%. This work provides new strategies for harnessing the full spectrum of solar energy and controlling the photothermal properties of nanofluids. Graphical Abstract Schematic diagram of photothermal conversion system of TiN@h-BN nanofluids.
研究领域:
材料科学
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能源工程
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纳米技术
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产品关联
DOI
高影响因子
Lubricants
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2024
·Vol. 12
·期 5
·163
·
IF 3.1
Yunqi Fang,Yang Sun,Fengqin Shang,Jing Zhang,Jiayu Yao,Zihan Yan,Hangyan Shen
Van der Waals heterostructures with incommensurate contact interfaces show excellent tribological performance, which provides solutions for the development of new solid lubricants. In this paper, a facile electrostatic layer-by-layer self-assembly (LBL) technique was proposed to prepare multi-layer van der Waals heterostructures tungsten disulfide/hexagonal boron nitride (vdWH WS2/h-BN). The h-BN and WS2were modified with poly (diallyldimethylammonium chloride) (PDDA) and sodium dodecyl benzene sulfonate (SDBS) to obtain the positively charged PDDA@h-BN and the negatively charged SDBS@WS2, respectively. When the mass ratio of PDDA to h-BN and SDBS to WS2were both 1:1 and the pH was 3, the zeta potential of PDDA@h-BN and SDBS@WS2were 60.0 mV and −50.1 mV, respectively. Under the electrostatic interaction, the PDDA@h-BN and SDBS@WS2attracted each other and stacked alternately along the (002) crystal plane forming the multi-layer (four-layer) vdWH WS2/h-BN. The addition of the multi-layer vdWH WS2/h-BN (1.0 wt%) to the base oil resulted in a significant reduction of 33.8% in the friction coefficient (0.104) and 16.8% in the wear rate (4.43 × 10−5mm3/(N·m)). The excellent tribological property of the multi-layer vdWH WS2/h-BN arose from the lattice mismatch (26.0%), a 15-fold higher interlayer slip possibility, and the formation of transfer film at the contact interface. This study provided an easily accessible method for the multi-layer vdWH with excellent tribological properties.
研究领域:
材料科学
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摩擦学
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纳米技术
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DOI
高影响因子
Advanced Science
·
2024
·
IF 14.3
Fuping Bian,Rui Huang,Xiaobin Li,Jiwen Hu,Shudong Lin
Composite polymer materials featured superior thermal conductivity, flame retardancy, and electromagnetic shielding performance are increasingly in demand due to the rapid development of highly miniaturized, portable, and flexible electronic devices. Herein, a facile and green ball milling shear method is utilized for generating MXene@Boron nitride (MXene@BN). The multi-functional fillers (MXene@BN) are constructed and incorporated into polydimethylsiloxane (PDMS) to prepare a multifunctional composite (PDMS/MXene@BN) for achieving improved electromagnetic interference (EMI) shielding performance and thermal conductivity as well as flame retardancy simultaneously. When the PDMS/MXene@BN composite has a MXene@BN loading of 2.4 wt.%, it exhibits a high thermal conductivity of 0.59 W m −1 K −1 , which is 210% higher than that of the pure PDMS matrix. This is attributed to its unique chestnut-like double-layer structure. With a smoke production rate (SPR) of 0.04 m 2 s −1 and total smoke production (TSP) of 3.51 m 2 , PDMS/MXene@BN 2.4 composite exhibits superb smoke suppression properties. These SPR and TSP values are 63.20% and 63.50% lower than the corresponding values of pure PDMS. Moreover, the EMI SE of the PDMS/MXene@BN 2.4 can reach 26.3 dB at 8.5 GHz. The work reported herein provides valuable insight into developing composites with multiple functions, which show strong potential for application in advanced packaging materials.
研究领域:
材料科学
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电子工程
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
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2017
·
IF 3.454
Y.L. Zhuang,T.S. Lin,S.J. Wang,P. He,D.P. Sekulic,D.C. Jia
The Ti 22 Si 78 (wt.%) braze was used to bond porous BN/Si 3 N 4 ceramic. The results revealed that the joint strength was low. In order to improve the joint strength, a carbon coated modification of the porous BN/Si 3 N 4 substrate, achieved by the pyrolysis of phenol-formaldehyde resin was suggested. The thickness of carbon layer was controlled by the volume ratio of phenol-formaldehyde resin and methyl alcohol (R/M). The effect of the carbon layer on the microstructure and mechanical properties of the joint was examined. It was established that the maximum joint strength was achieved at the level of 80 MPa (as opposed to the uncoated joint with only 30 MPa) when R/M was 1:2, at the given brazing temperature. The improvement of the joint strength is attributed mainly to the formation of a SiC infiltration reaction layer, a significant population of SiC nanowires, as well as TiN 0.7 C 0.3 and TiB 2 particles.
研究领域:
材料科学
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工程学
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DOI
高影响因子
Journal of Materials Chemistry C
·
2024
·
IF 5.7
Qiuqi Zhang,Xiao You,Huiying Ouyang,Yuanhang Yang,Zhenzhong Xing,Haodong Gu,Li Tian,Qingliang Shan,Xiangyu Zhang,Jinshan Yang,Shaoming Dong
In this work, a high-performance electromagnetic wave (EMW) absorber is prepared by the in situ growth of BN and SiC into a self-assembled 3D graphene skeleton via chemical vapor infiltration (CVI). The porous conductive graphene network extends the transmission path of incident microwaves by multiple scattering, and the ceramic coating effectively improves the impedance matching degree. Notably, the EMW absorbing performance of 3D-rGO/BN/SiC can be regulated by the high-temperature oxidation in air. Compared to the original absorbers, after being oxidized at 600 °C for 4 h in air, the optimal RLmin of the composites drops to −47.1 dB and the broadest EAB reaches 11.96 GHz, which can be attributed to the enhanced impedance matching degree. The controllable fabrication of 3D-rGO/BN/SiC composites can provide a guideline for rational design and fabrication of high-performance EMW absorbing materials in practical applications under medium oxidizing temperature.
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
CHEMICAL ENGINEERING JOURNAL
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2022
·
IF 16.744
Weijie Zhang,Shunshun Zhao,Yupeng Xing,Hongjie Qin,Qiling Zheng,Penghui Zhang,Shouwei Zhang,Xijin Xu
The sustainable conversion from solar energy to chemical energy is realized by using photocatalytic technology to produce hydrogen and hydrogen peroxide. In this work, the construction of a direct Z-scheme heterojunction is of great significance for improving the efficiency and stability of photocatalytic hydrogen evolution (PHE) and photocatalytic hydrogen peroxide production (PHP). In this study, P-doped h-BN (PBN) nanosheets are used to support the in-situ growth of ZnIn 2 S 4 nanoflowers via wet chemical method, and sandwich-like PBN/ZnIn 2 S 4 hierarchical heterostructures are successfully synthesized. The PHE performance of PBN/ZnIn 2 S 4 (∼59.46 μmol/h) is ∼ 2.35 times than that of the original ZnIn 2 S 4 (∼25.27 μmol/h), and the PHP performance (∼122.82 μmol/L/h) is 39.37 times than that of PBN (∼3.12 μmol/L/h). The excellent photocatalytic performance of PBN/ZnIn 2 S 4 can be attributed to the following points: (1) the acceleration of the separation of photogenerated electron-hole pairs induced by the formation of Z-scheme heterostructure; (2) reasonable design and construction of sandwich-like PBN/ZnIn 2 S 4 hierarchical heterostructure; (3) the promotion the migration and separation of photogenerated carriers by the built-in electric field. This work provides new ideas for the development of high-efficiency PHE and PHP Z-scheme heterojunction photocatalyst design.
研究领域:
材料科学
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能源化学
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DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2022
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IF 5.518
Li Li,Junjie Chen,Guodong Sheng,Yixin Pan,Xiaojie Guo
In this study, a novel nanocomposite (FeS@h-BN) that FeS nanoparticles anchored onto h-BN nanosheets was synthesized for chromium (Cr(VI)) removal in aqueous solutions and characterized by SEM, TEM , XRD , FTIR, Zeta, and XPS . The effect of removal parameters including initial pH, temperature, FeS@h-BN dosage, the initial concentration of Cr(VI) and contact time were investigated. Experiment results revealed that h-BN as a stabilizer for FeS had good stability and effectively reduced FeS agglomeration. The remarkable performance of removing total Cr in aqueous solution was obtained by effectively converting Cr(VI) to Cr(III) on FeS and simultaneously adsorbing Cr(III) on h-BN. The adsorption capacity of FeS@h-BN for Cr(VI) was extremely sensitive to the pH and the optimum adsorption was 399.72 mg/g at pH of 1.0. In addition, the efficiency of removing Cr(VI) by FeS@h-BN increased with the increase of adsorbent dosage and Cr(VI) concentration, and the efficiency reached 100% at an adsorbent dosage of 0.30 g/L. The pseudo-second-order kinetic model can fully explain the experimental rate data. The mechanism of FeS@h-BN to remove Cr(VI) was adsorption and chemical reduction, of which chemical adsorption was the main one. These results revealed that h-BN as a stabilizer can improve the FeS stability and reactivity for the rapid removal of Cr(VI) contamination in water solution.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
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2020
·Vol. 126
·期 7
·1-9
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IF 1.81
He Bing,He Wenhui,Wang Yawen
Semiconductor photocatalyst as a new type of green and sustainable energy material has extensively used in wastewater and gas treatment. In this work, we prepared Pt/h-BN/BiOBr composite by an alcohol-soluble hydrolysis-assisted photoreduction method. The photocatalytic activity was evaluated by the degradation of bisphenol A under simulated sunlight, and the degradation efficiency of BiOBr, h-BN/BiOBr, Pt/BiOBr, and Pt/h-BN/BiOBr were 55.13%, 74.91%, 89.00%, and 98.54%, respectively. The results showed single composited with h-BN or Pt could improve the photocatalytic performance of BiOBr, while double composited with h-BN and Pt could play a synergistic effect on further improving the activity. The interaction between h-BN and BiOBr was electrostatic interactions, and that Pt as a plasma metal was coupling with BiOBr due to its localized surface plasmon resonance (LSPR) effect. The composition, morphology, optical property, and separation efficiency of photo-induced carriers and dominant active radicals were investigated. Based on the results, a possible mechanism was proposed. The excellent photocatalytic activity of Pt/h-BN/BiOBr composite photocatalyst could be attributed to the broadened light-response range after Pt loading, and enhanced electron–hole separation efficiency due to the electron capturer role of Pt and the hole transfer function of h-BN.
研究领域:
环境科学
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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
CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Mingtan Wang,Guoqing Xiao,Fei Wang,Chunlin Chen,Junjie Cao,Jing Gou,Xiyi Ma,Hongxin Yan
Porosity and cracks during the curing process of waterborne epoxy resins have severely limited their application. In this study, Zn 2+ was adsorbed on the surface of BN through a coordination reaction. And the electronegativity difference between Hexamethylene diamine tetramethylene phosphonic acid (Hdtmp) and Zn 2+ was exploited to make it forming a stable complex on the surface of BN. Corrosion-resistant composite coatings were prepared by doping the synthesized BN@Zn-Hdtmp hybrid materials into waterborne epoxy resin. The anticorrosion mechanism and anticorrosion properties of the BN@Zn-Hdtmp hybrid materials were predicted by molecular dynamics and density functional theory. Furthermore, after immersion in a 3.5 % NaCl solution for 45 days, the BN@Zn-Hdtmp/EP composite coating exhibited a significant decrease in resistance, from 3.371 × 10 9 Ω cm 2 to 1.845 × 10 7 Ω cm 2 . This represents a two-order-of-magnitude enhancement in resistance compared to pure EP. Additionally, the surface roughness of the carbon steel coated with BN@Zn-Hdtmp/EP was found to be lower than that of EP. EIS analysis of scratched coatings, salt spray tests, SEM images of the corroded areas and quantitative EDS spot scan analyses showed that the composite coatings have excellent self-healing properties. The crosslink ability between BN@Zn-Hdtmp and EP was demonstrated by DFT calculations as well as TGA tests to provide a new crosslinking mode and enhance the densification of EP. In the mechanical property tests, the tensile strength, elongation at break, and adhesion of the composite coatings were better than those of pure EP. The above results indicate that BN@Zn-Hdtmp/EP has excellent anticorrosive and mechanical properties, which provides a new method to achieve long-lasting anticorrosive protection of waterborne epoxy resin.
研究领域:
材料科学
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腐蚀与防护
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表面工程
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产品关联
DOI
高影响因子
Journal of Energy Chemistry
·
2021
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IF 9.676
Yaoxin Wang,Jiandian Wang,Ping Zheng,Changyong Sun,Junyin Luo,Xiaowei Xie
Propane dehydrogenation (PDH) provides an alternative route for producing propylene. Herein, we demonstrates that h-BN is a promising support of Pt-based catalysts for PDH. The Pt catalysts supported on h-BN were prepared by an impregnation method using Pt(NH 3 ) 4 (NO 3 ) 2 as metal precursors. It has been found that the Pt/BN catalyst undergoing calcination and reduction is highly stable in both PDH reaction and coke-burning regeneration, together with low coke deposition and outstanding propylene selectivity (99%). Detailed characterizations reveal that the high coke resistance and high propylene selectivity of the Pt/BN catalyst are derived not only from the absence of acidity on BN support, but also from the calcination-induced and reduction-adjusted strong metal-support interaction (SMSI) between Pt and BN, which causes the partial encapsulation of Pt particles by BO x overlayers. The BO x overlayers can block the low-coordinated Pt sites and constrain Pt particles into smaller ensembles, suppressing side reactions such as cracking and deep dehydrogenation. Moreover, the BO x overlayers can effectively inhibit Pt sintering by the spatial isolation of Pt during periodic reaction-regeneration cycles. In this work, the catalyst support for PDH is expanded to nonoxide BN, and the understanding of SMSI between Pt and BN will provide rational design strategy for BN-based catalysts.
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
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2019
·
IF 4.029
Lu Zilong,Yue Jianling,Fu Zeyu,Huang Xiaozhong,Yang Haitang
SiC f /BN/SiC mini-composites comprising single tow SiC fibre-reinforced SiC with chemical vapour deposited (CVD) BN interface layers were fabricated. The mechanical performance and binding strength of the composites and the fibre/interface for the oxidized SiC f /BN/SiC mini-composite samples (oxidation at 1000, 1200, 1300, 1400 and 1500 °C in air for two hours) were investigated by tensile tests and fibre push-out tests, respectively. The value of oxidation mass change was also measured. Some unusual phenomena for the SiC f /BN/SiC mini-composites oxidized at 1000 °C were discovered in this work. The tensile strength reached a maximum value, and the mass gain rate showed as a singular negative value, while the shear strength between the fibre and the matrix was moderate. Scanning electron microscopy, energy dispersive spectrometry, infrared spectroscopy and X-ray diffraction characterization methods were used to reveal the microstructural evolution and investigate the unusual phenomenon during oxidation procedures. This work will provide guidance for predicting the service life of SiC f /BN/SiC composite materials and may enable these materials to become a backbone for thermal structure systems in aerospace applications .
研究领域:
材料科学
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高温复合材料
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航空航天材料
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表面工程
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结构表征
✓ 已验证
DOI
高影响因子
MATERIALS & DESIGN
·
2019
·
IF 5.77
Haixia Yang,Chunming Li,Xiandong Yue,Jianchun Huo,Feng Ye,Jingxiao Liu,Fei Shi,Jie Ma
Although pure silicon oxycarbide (SiOC) aerogels have unique properties of low density and high temperature resistance, they are still difficult to apply at a large scale due to brittleness. To overcome this drawback, a strong boron nitride/silicon oxycarbide (BN/SiOC) aerogel composite with high-temperature resistance and thermal insulation was prepared by the sol-gel method and pyrolysis of the precursor aerogel. The microstructural, mechanical and thermal insulation properties of the composites were investigated, and the effect of the BN content on the microstructure and properties was also clarified. The results indicate that the obtained mesoporous composites exhibit low thermal conductivity (0.04–0.20 Wm −1 K −1 ) and high-temperature resistance (∼1300 °C). As the BN content increased from 0 to 15 vol %, the compressive strength of the composites increased from 2.2 to 20.3 MPa. The obtained composites exhibit considerable promise in high-temperature thermal insulation applications.
研究领域:
材料科学
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高温材料
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纳米材料
✓ 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）