JOURNAL OF ALLOYS AND COMPOUNDS
·
2023
·
IF 6.2
Tarek A. Gad-Allah,Ruiyang Zhang,Yi Wang,Ying Zhou
Various factors control the photocatalyst efficiency including the lifetime of photogenerated charge carriers, photocatalyst surface energy, and light harvesting efficacy. In this study, the defective (001)-TiO 2 -x/h-BN composite was synthesized by a facile one-pot method to merge the fantastic features of the reactive metastable (001) facet and self-defects in TiO 2 anatase crystals with the 2D h-BN. Pure anatase phase of TiO 2 was obtained by the suggested preparation method, which contains ∼33 % of the exposed (001) facet. The predominancy of oxygen vacancy in TiO 2 crystals was proved experimentally and theoretically by the DFT calculations. The defects in TiO 2 along with the incorporated h-BN caused better light harvesting and longer charge lifetime. The prepared defective (001)-TiO 2 -x/h-BN was applied efficiently for NO removal with very limited release of the toxic NO 2 by-product as an environmental application. The detected oxygen vacancy in TiO 2 along with h-BN were found to play a synergistic enhancement for NO removal. However, more defects reduced the overall activity because of rapid oxidation of oxygen vacancies on surface of the photocatalyst. To sum up, the defective (001)-TiO 2 -x/h-BN composite can be considered as a promising material for environmental applications.
研究领域:
环境科学
·
材料科学
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DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2022
·
IF 9.965
Kunpeng Qian,Qianfan Zhou,Sineenat Thaiboonrod,Jianhui Fang,Miao Miao,Hongmin Wu,Shaomei Cao,Xin Feng
With the development of electronic equipment, heat problem and electromagnetic pollution severely affect both their functions and human health, which leads to great interests in developing materials synchronously with outstanding thermal conductivity and electromagnetic interference (EMI) shielding performance. Here, ultrathin Ti 3 C 2 T x /h-BN two-dimensional (2D) heterostructure films were prepared via coulombic assembly between Ti 3 C 2 T x MXene and h-BN nanosheet through ultrasonic blending. After the addition of h-BN nanosheet as thermal conductive nanofillers, the hybrid films achieved a higher value of thermal conductivity, compared to Ti 3 C 2 T x composite film without h-BN. The higher thermal conductivity offered by h-BN enables the Ti 3 C 2 T x /h-BN films have good potential for EMI shielding applications on wearable and portable electronic devices. When the mass ratio of Ti 3 C 2 T x /h-BN is 7:3, the hybrid film with the thickness of 47.60 µm exhibited electrical conductivity of 57.67 S/cm and the maximum EMI shielding effectiveness of 37.29 dB.
研究领域:
材料科学
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电子工程
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DOI
高影响因子
RENEWABLE ENERGY
·
2022
·
IF 8.634
Rui Chen,Qinpan Qiu,Xiao Peng,Chao Tang
Natural ester is regarded as a potential alternative to mineral insulating oil and has a wide range of applications in power system , but its electrical properties and thermal conductivity still need to be improved. Nano modification technology can improve the performance of natural ester to ensure the stability and reliability of natural ester in power equipment. In this study, nano modified natural ester is prepared with APTES surface modified h-BN, and the mechanism of enhancing the properties of natural ester is explored from the microscopic perspective by molecular simulation. The experimental results showed that nano h-BN had good dispersion stability in natural ester after surface modification with APTES. The electrical properties and thermal conductivity of the nano modified natural ester have been greatly improved, and the relative optimal doping concentration of nanoparticles is 0.03 g/L. The simulation results show that the interfacial thickness between nanoparticles and natural ester is larger and more tightly bound after surface modification, which is beneficial to reduce thermal resistance and improve thermal conductivity of natural ester insulating oil. The traps at the interface between nanoparticles and natural ester can capture free electrons in the oil, thus improving the breakdown voltage of natural ester insulating oil.
研究领域:
材料科学
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电力工程
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产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2021
·Vol. 32
·期 17
·21858-21868
·
IF 2.478
Wang Jinmao,Yan Hong,Long Yumei,Li Weifeng
In this work, a series of h -BN/ α -SnWO 4 (BN/SW) nanocomposites with different h -BN concentrations (0.3–1.0 wt%) were prepared through a hydrothermal method. The composition, structure and morphology of BN/SW nanocomposites were systematically investigated. The formation of BN/SW heterojunction was evidenced by Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS) and high-resolution transmission electron microscopy (HRTEM). The BN/SW composites showed plate-to-plate structure consisting α -SnWO 4 and h -BN nanoplates. The optical and photoelectrochemical studies revealed that the decorating of h -BN can significantly facilitate the separation of the photo-created charge carries due to the formation of heterostructure. As a result, BN/SW hetero-structure exhibited the superior photocatalytic performance under visible light, which was confirmed by the photo-degradation of methyl orange (MO) and tetracycline (TC). Especially, the BN/SW-0.5 sample has the best rate constant of 0.0323 min −1 , which is 4.6 times larger than that of α -SnWO 4 . Based on trapping experiment, the h + radical was identified as the dominant reactive species, and ·O 2 − and ·OH also made contribution to the photocatalysis. In addition, the photocatalytic enhancement mechanism of BN/SW heterojunction was proposed. This study shed light on the roles of h -BN in the design of photocatalysts with high-performance.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
·
2024
·
IF 5.6
Qi Wang,Hao-Yue Wang,Nuerguli Kari
Rapid and incredibly sensitive analyte detection is crucial in a variety of settings, including medical diagnostics. However, conventional surface plasmon resonance (SPR) sensors cannot effectively solve the issue of low sensitivity when assaying trace analytes. In this work, the rare Earth oxide Lu2O3 is first introduced to modify fiber optic SPR sensor. By utilizing the inherent advantages of Lu2O3, including high dielectric constant, high breakdown field strength, and high photoelectric conversion efficiency, the electric field around the sensor is effectively increased and high sensitivity detection is achieved. Experimental results show sensitivity of the sensor modified with Lu2O3 nanomaterial reaches 12133.78 nm/RIU in the interval of 1.3614–1.3756. The hexagonal boron nitride (h-BN) is subsequently introduced to further enhance electric field using the charge transfer mechanism. The sensitivity reaches 15065.92 nm/RIU, 3.96 times better than conventional U-shaped fiber SPR sensors. The sensor is compact designed with high sensitivity. There is significant potential for improving the sensitivity aspect of analyte detection.
研究领域:
生物医学工程
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光学传感
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材料科学
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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
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电子工程
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产品关联
DOI
PubMed
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
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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
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产品关联
DOI
高影响因子
Materials
·
2023
·Vol. 16
·期 14
·4979
·
IF 3.4
Wen Zhong,Jiazhi Dong,Siqiang Chen,Zhe Tong
The synergistic effect of different types of solid particles in liquid lubricants is of great interest. In this work, g-C3N4nanosheets were initially prepared using a calcination method and then as-prepared, and h-BN were used as lubricating additives to the white oil. A comparison between the mixed additives and the single g-C3N4or h-BN additives revealed that the base oil with the addition of g-C3N4and h-BN showed the best lubricating properties. The results show a 12.3% reduction in friction coefficient, resulting in a 68.6% reduction in wear rate compared to the white oil when filled with 0.5 wt% g-C3N4and h-BN (1:1 by weight). Moreover, the addition of g-C3N4and h-BN improves the high-temperature lubrication properties of the white oil. However, the friction coefficient and wear rate increase with increasing oil temperature. The large contact area between g-C3N4and its sliding counterpart and the strong adhesive force between h-BN and its sliding counterpart improve the film formation efficiency, leading to enhanced tribological properties under oil lubrication conditions.
研究领域:
材料科学
·
机械工程
·
表面工程
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产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Yunzi Li,Fei Chen,Xiaoyu Li,Qiang Shen,Lianmeng Zhang
Ceramic/metal composites, as high-temperature structural materials, have limited applications because of their poor machinability . AlN/Mo/Mo 2 B machinable composites were fabricated by adding h-BN to AlN/Mo composites by plasma-activated sintering at various temperatures and at an axial pressure of 30 MPa under argon atmosphere. The sample sintered at 1500 °C exhibited excellent machinability for cemented carbide tools, with a bending strength of approximately 500 MPa and a Vickers hardness value of 9.34 GPa. The effects of sintering temperature on the microstructure, mechanical properties, and machinability were investigated, and the reactions introduced by adding h-BN were studied. These reactions reinforced the composite and newly introduced a Mo 2 B phase, which showed better ability to deflect cracks and prevent them from moving deep inside the composite, thus improving its machinability. This research provides a possible solution for improving the machinability of ceramic/metal composites without sacrificing the strength .
研究领域:
材料科学
·
机械工程
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2020
·
IF 16.683
Wei Li,Xiao Wang,Qiong Ma,Fei Wang,Xiao-shan Chu,Xue-chuan Wang,Chuan-yi Wang
Solar light driven hydrogen evolution is a prospective strategy to solve the energy problem. However, the poor photoresponse, low photocurrent density and easy electron-hole recombination remarkably restrict the HER activity of the conventional photocatalyst. Herein, we constructed a CdS@hexagonal boron nitride (h-BN) heterostructure on reduced graphene oxide (rGO) to synthesize a ternary CdS@h-BN/rGO catalyst via a structural reconstruction strategy. The CdS@h-BN heterointerface promoted the electrons transferring to the CdS active centers from the valence band of h-BN under photoinduction, overcoming the wide bandgap defect of pristine h-BN. The easily photoexcited property of CdS cocatalyst resulted in superhigh photocurrent density (2.7·μA cm −2 ) under simulated solar light, which was 3.3-fold greater of pristine CdS NPs. Meanwhile, the interfacial interactions of three components remarkably restrained the carriers recombination. Hence, the resultant ternary hybrid catalyst presented remarkably improved photoresponse and interfacial conductivity, thereby the optimal catalyst represented remarkably enhanced HER activity (6465.33 μmol h −1 g −1 ) under simulated solar light, which was about 10.9-fold greater of the pristine CdS NPs and 218.3-fold greater of the optimal h-BN/rGO hybrid. About 19.8 % of apparent quantum yield was achieved under illumination of λ =420 nm, and the excellent regenerability and durability were represented during six cycles and 20 h of continued illumination. Thereby, this study provides a prospective idea for constructing low-cost nonprecious metal based photocatalyst with highly efficient HER performance.
研究领域:
材料科学
·
能源科学
·
光催化技术
✓ 已验证
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2022
·
IF 6.364
Mao chen,Fan Zhang,Hailong Wang,Gang Shao,Bingbing Fan,Rui Zhang,Hongxia Li,Yongqiang Chen
The dense h-BN/ZrO 2 (30 wt%) composites without additives were rapidly fabricated by spark plasma sintering . The relative density, apparent porosity, fracture toughness, flexural strength , phase composition and microstructure of h-BN/ZrO 2 composites were systematically investigated. Besides, the corrosion resistance of h-BN/ZrO 2 composites in molten steel was also studied in detail. Especially, the h-BN/ZrO 2 composites were sintered at 1800 °C exhibiting a relative density of 96.6% and the flexural strength of ≈ 157 MPa. The corrosion of h-BN/ZrO 2 composites was mainly due to the oxidative decomposition of BN, and the corrosion process was clarified by a parabolic law. The excellent corrosion resistance of the h-BN/ZrO 2 composites was attributed to ZrO 2 residual layer formed at the interface. The corrosion thickness of h-BN/ZrO 2 composites was only ∼116 µm even using the longest corrosion time (80 min). The composites could be a promising candidate material applied to fabricated thin strip continuous casting side sealing plates.
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
危险品化学品经营许可证（带存储）