COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2022
·
IF 5.518
Qian Zhang,Zhiwei Guo,Yujie Yang,Yanxiang Li,Chuanfang Yang,Wangliang Li
Surfactants in ultra-low sulfur diesel (ULSD) can improve the stability of the emulsified water droplet by forming a thin film at the water-fuel interface. Emulsified water droplets block the oil spray nozzle and break down the engine, which need to be removed. For colliding emulsified water droplets, surfactant film with high viscoelastic modulus provides an obstacle to their coalescence. Micro/nanosized-SiO 2 particles were added into ULSD to interrupt the arrangement of the surfactant film. After adding with 20 nm SiO 2 , the interfacial tension of water-monoolein-ULSD increased from 16.0 mN/m to 21.4 mN/m, and its viscoelastic modulus decreased from 17.1 mN/m to 10.9 mN/m, a decrease of 36.3%. It proved that the addition of nanosized SiO 2 into water-monoolein-ULSD system increased the interfacial tension and reduced the viscoelastic modulus of the monoolein film. However, after adding nanosized SiO 2 , the viscoelastic modulus of the water-PETO-B-ULSD layer had no significant changes. Therefore, we concluded that 20 nm SiO 2 disturbed the dense packing of monoolein as its adsorption to surfactants and the electrostatic repulsion force between them and the hydrophobic group, resulting in a decrease in elastic modulus . However, PETO-B had a complex branched structure leading to a loose packing, which had unoccupied adsorption sites and barely affected by the intrusion of 20 nm SiO 2 . Therefore, this research provided a strategy to add nanosized-SiO 2 into W/O emulsions containing monoolein-like surfactant to reduce its stability.
研究领域:
化学工程
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材料科学
·
表面科学
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产品关联
DOI
高影响因子
CRYSTENGCOMM
·
2025
·
IF 2.6
Kaiwen Wu,Jichao Shi,Daqing Wang,Honghao Ni,Runping Jia,Yufeng Liu,Lin Lin,Dandan Wu,Shufang Chang,Yaqi Wang,Qing Xin
Magnetic iron oxide is a typical narrow-band gap semiconductor photocatalyst, but its inherent magnetic aggregation effect and high electron–hole recombination rate seriously affect its photocatalytic performance. Here, α-Fe2O3/SiO2 composite aerogels were prepared by combustion technology for the first time. The unique structure of α-Fe2O3/SiO2 composite aerogels with amorphous silica coated with nanocrystalline iron oxide was confirmed. The composite aerogels exhibited a high specific surface area (479 m2 g−1 when calcined at 500 °C), so that they have excellent adsorption properties for organic pollutants (MB, RhB and TC) and Cr(VI). The composite aerogels with a Fe : Si molar ratio of 1 : 2 showed the best visible light photocatalytic properties for MB, RhB and TC. Based on the study of the band gap width, photocurrent density, transient photocurrent response, impedance of photocatalysts, and the unique structure of the composite aerogels, the mechanism of photocatalytic enhancement of composite aerogels was proposed. Finally, the mechanism of the preparation of α-Fe2O3/SiO2 composite aerogels by combustion synthesis was analyzed. It is a potential technology for preparing high performance composite aerogel photocatalysts by high efficiency combustion technology.
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
European Physical Journal-Special Topics
·
2025
·
IF 2.3
Zhang Yu,Wen Yunli,Dai Yuxiang,Li Guishun,Yun Junqiang,Jing Chengbin
The susceptibility to optical instability of perovskite nanocrystals (NCs) under ambient conditions is a serious hindrance for practical applications. The conventional SiO 2 coating method for enhancing stability suffered from long reaction times and complicated preparation procedures. In this study, a facile and convenient room-temperature one-pot approach was developed to fabricate CsPbBr 3 /SiO 2 NCs, which involves the addition of tetramethoxysilane (TMOS) in advance. Owing to surface passivation, the PLQY of the CsPbBr 3 /SiO 2 NCs increased to 90% from 70% of the primitive CsPbBr 3 NCs. The SiO 2 layer formed by the TMOS hydrolysis and condensation reactions also protect the CsPbBr 3 NCs from external environment stimuli. Compared with the pristine CsPbBr 3 NCs, the air stability, structural stability, polar solvent resistance, thermal stability, and UV resistance stability of the CsPbBr 3 /SiO 2 NCs are markedly enhanced. Also, the CsPbBr 3 /SiO 2 NCs can be used as green phosphors for white light-emitting diode (WLED), which exhibits a luminous efficiency of 40 lm/W.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Shiha Huang,Bin Ya,Bingwen Zhou,Yunfeng Liu,Xingguo Zhang
The application of Fe-based amorphous microspheres in high-performance electromagnetic wave absorbing materials is significantly limited by a single loss mechanism. Utilizing interfacial engineering and magnetic-dielectric synergistic effect is a viable approach to enhance microwave absorption. In this work, FeSiBCuNbZr amorphous microspheres were synthesized using single copper roller melt-spinning method and ball mill method. The finding reveals that the incorporation of SiO 2 and TiO 2 (B) (bronze phase TiO 2 ) shells notably enhances polarization loss and conductive loss. FeSiBCuNbZr@SiO 2 @TiO 2 (B) amorphous composites exhibited a minimum reflection loss value of −64.89 dB at a thickness of 2.17 mm and an effective absorption bandwidth (EAB) of 8.08 GHz covering 9–18 GHz at a thickness of 1.9 mm. The exceptional wave absorption performance is ascribed to the combined effect of magnetic loss in the FeSiBCuNbZr amorphous core and dielectric loss from the double-shell structure, while maintaining favorable impedance matching. This work provides a new core–shell FeSiBCuNbZr amorphous composites for efficient electromagnetic wave absorption.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2020
·
IF 5.006
Xuefei Wang,Yong Men,Jinguo Wang,Shuang Liu,Qiaoling Song,Mei Yang
Catalytic transformation of ethanol has been studied over a series of MgO-SiO 2 composite catalysts with different ZnO loadings. Vast differences in product selectivity are obtained by varying ZnO loadings in enabling the control over product distribution. Our results reveal that MgO-SiO 2 composite catalysts with low ZnO loadings tend to show an enhanced efficiency for C C bond coupling and exceptionally high selectivity to 1,3-butadiene whereas the high ZnO loadings favor the formation of acetaldehyde via dehydrogenation. Thorough analysis of characterization results via XRD, BET, IR, TPD, and 29 Si MAS NMR indicates that ZnO loading influences the extent of MgO and SiO 2 interaction during preparation, and the surface acid-base chemistry, which were both found to correlate with the catalytic performance. This study proposes that the Mg O Si interfacial structure formed by the strong MgO and SiO 2 interaction at low ZnO loadings is of prime importance for the formation of 1,3-butadiene, benefiting from the desirable properties of balanced dehydrogenation and C C bond coupling while excess ZnO loadings destroy the Mg O Si interfacial bonds over the MgO-SiO 2 composite catalysts, which are the key structures required for C C bond growth.
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
RSC Advances
·
2019
·Vol. 9
·期 1
·498-506
·
IF 3.049
Wei Wang,Ang Zheng,Yifan Jiang,Dongsheng Lan,Fenghua Lu,Lelin Zheng,Lin Zhuang,Ruijiang Hong
Monodisperse colloidal particles have promising applications in electrophoretic displays with vivid colors, reversibility and low switching times. In this study, a facile, effective and large-scale strategy for preparing size-controlled Fe3O4@SiO2 particles is reported. Multiple Fe3O4 particles were synthesized by a modified solvothermal method using sodium citrate as a surface modifier with a binary solvent, and were then coated with a SiO2 layer to obtain a highly negatively charged surface via a modified Stöber method. Owing to the easily controlled sizes and sufficient surface charges, Fe3O4@SiO2 particles can be assembled into colloidal amorphous arrays with the balance of electrostatic repulsion and electrophoretic forces. The reflections cover wavelengths ranging from 802 to 453 nm, and were optimized by investigating the dependence of the particles on variables such as particle size, particle volume fraction, and electric field intensity. The large-scale preparation of electrically responsive Fe3O4@SiO2 particles facilitates an electrophoretic display with broad-range colors, showing the practical potential in industrial application.
研究领域:
材料科学
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纳米技术
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显示技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Surfaces and Interfaces
·
2023
·
IF 6.2
Chengmin Hou,Ze Fan,Jiaqi Yang
Most of the super hydrophobic cotton fabric surfaces changed the original properties of cotton fabric and cannot be continuously used for oil-water separation. In this paper, the fluorine-containing epoxy polymer P(GMA- r -DFMA) was reacted with KH550 modified nano-SiO 2 to obtain an organic-inorganic hybrid super hydrophobic solution. By dipping process, the super hydrophobic cotton fabric surface was obtained. P(GMA- r -DFMA) can reduce the surface energy of cotton fabric, and modified silica can improve the surface roughness of cotton fabric to achieve super hydrophobic effect. The optimum parameters (polymer concentration, soaking time, drying time and drying temperature) for constructing super hydrophobic cotton fabric surface were explored. The optimal parameters are polymer concentration 5 mg/mL, soaking time 5 h, drying time 4 h, and drying temperature 120 °C. Under the optimal conditions, the water contact angle of the modified cotton fabric surface is 162±3 o and the water rolling angle is 10±1 o . The study on surface self-cleaning property of modified cotton fabric shows that modified cotton fabric can be restored to clean state after being soiled by toner and washed by deionized water. When the oils were n -hexane, n -octane and trichloromethane, the oil-water separation efficiency of the modified cotton fabric could reach 98%, 98% and 96%, and the effect was stable. The surface of modified cotton fabric has obvious silver mirror phenomenon. The results of Scanning Electron Microscopy showed that the surface of cotton fabric was smooth before modification, but many small bumps and folds were added on the fabric surface after super hydrophobic modification, and the roughness became larger. The super hydrophobic coating is very thin and does not change the color, softness and other properties of the cotton fabric.
研究领域:
材料科学
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纺织工程
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产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2023
·
IF 6.2
Xinli Ye,Jianqing Xu,Shan Li,Xiaomin Ma,Bangxiao Mao,Junxiong Zhang,Kai Zheng
With the widespread application of radar detection systems in the military field, the development of radar stealth technology can effectively reduce the characteristic signals of targets, which was of great significance for the protection of important military targets. In this paper, the resorcinol/formaldehyde (RF) reinforced silica aerogel (RF/SiO 2 ) was synthesized successfully. The RF was introduced into the sol/gel technology to build a porous skeleton, and the SiO 2 aerogel was prepared by atmospheric pressure drying. The RF/SiO 2 aerogel was then heat treated, and the microstructure and physical properties of the RF/SiO 2 aerogel before and after heat treatment were characterized to study the influence of the heat treatment temperatures on the RF/SiO 2 aerogel. With the increase of the heat treatment temperature, its electromagnetic wave absorption performance had been significantly improved. When the heat treatment temperature reached 1500 ℃, the RF/SiO 2 aerogel possessed a minimum reflection loss of − 36.42 dB at 1.95 mm and an effective bandwidth of 2.94 GHz at 2.00 mm within the radar band of 8.00–12.00 GHz. In addition, this paper used CST software to optimize and design the periodic structure of metamaterial based on the RF/SiO 2 aerogel. The optimization design of the patch size and substrate thickness on the substrate surface provided a reference for the future application of this material in specific radar stealth fields.
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
Analytical Methods
·
2015
·Vol. 7
·期 8
·3486-3492
·
IF 1.821
Houmei Liu,Yong Guo,Xusheng Wang,Xiaojing Liang,Xia Liu
In this paper, a novel sorbent, nano-Al2O3 coated mesoporous silica (Al2O3/SiO2), was prepared and used as a sorbent for solid-phase extraction of flavonoids. The synthesized sorbent material was characterized by X-ray photoelectron spectroscopy, energy dispersive spectroscopy and inductively coupled plasma emission spectrometry. The extraction properties of the resultant sorbent were evaluated by using four flavonoids (myricetin, quercetin, luteolin and kaempferol) as the test analytes. The extraction efficiencies of Al2O3/SiO2 were apparently superior to those of commercial C18 sorbents. Under optimal conditions, good linearities with R2 ranging from 98.8% to 99.8% were obtained and the LODs and LOQs were found to be in the range of 0.5–1 μg L−1 and 2.5–3 μg L−1, respectively. The proposed method was successfully applied for the real sample analysis of wild honey and red grape juice.
研究领域:
分析化学
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材料科学
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食品科学
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产品关联
DOI
高影响因子
JOURNAL OF POROUS MATERIALS
·
2019
·Vol. 27
·期 2
·429-440
·
IF 1.947
Wang Yunjie,Yuan Hong,Zhang Zhi,Ke Yihu
A series of ordered mesoporous S 2 O 8 2−/ ZrO 2 –SiO 2 (OMSZS) solid superacids with different calcination temperatures (400–650 °C) was synthesized using zirconium n-propoxide and tetraethyl orthosilicate as the raw materials and P123 as a structure-directing agent by solvent evaporation-post-dipping method. Transmission electron microscopy and small-angle X-ray diffraction results showed that the OMSZS were all ordered. The nitrogen adsorption results indicated that the specific surface area of OMSZS could reach up to 331–385 m 2 /g, whereas the average pore diameters were in the range of 3.1–3.2 nm. The pyridine infrared results mainly displayed Lewis acids, and the ammonia (NH 3 )-temperature programmed desorption characterization showed that the NH 3 desorption of the OMSZS calcined at 550 °C was 61 cm 3 /g STP. The catalytic performance of the OMSZS was investigated by the transesterification reaction of waste frying oil and methanol. The yield of fatty acid methyl ester could reach up to 94% at 200 °C reaction temperature for 6 h. After repeated use for four times, the catalyst still featured good activity and the yield was 78%.
研究领域:
材料科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2022
·
IF 10.753
Jialong Wu,Xiaozhen Ma,Pitchaimari Gnanasekar,Fan Wang,Jin Zhu,Ning Yan,Jing Chen
Superhydrophobic polyurethane foam is one of the most promising materials for oil-water separation. However, there are only limited studies prepared matrix superhydrophobic foams as adsorbents. In this paper, SiO 2 modified by 1H, 1H, 2H, 2H-perfluorododecyl trichlorosilane (F-SiO 2 ) was added into the lignin-based foam matrix by a one-step foaming technique. The average diameter of F-SiO 2 was about 480 nm with an water contact angle (WCA) of 160.3°. The lignin-based polyurethane foam with F-SiO 2 had a superhydrophobic water contact angle of 151.3°. There is no obvious change in contact angle after 100 cycles of compression or after cutting and abrasion. Scanning electron microscopy (SEM) analysis showed that F-SiO 2 was distributed both on the surface and inside of the foam. The efficiency for oil-water separation reached 99 %. Under the light intensity of 1 kW/m 2 , the surface temperature of the lignin-based foam rose to 77.6 °C. In addition, the foam exhibited self-cleaning properties and degraded within 2 h in an alcoholic alkali solution. Thus, in this study, we developed a novel matrix superhydrophobic lignin-based polyurethane foam with an excellent promise to be used as oil water separation adsorbents in industrial wastewater treatment and oil spill clean-up processes.
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2023
·
IF 9.5
Huixian Zhou,Yiqing Zeng,Zexian Low,Feng Zhang,Zhaoxiang Zhong,Weihong Xing
Developing cost-effective and high-efficient air purification materials for enhancing the indoor air quality has been an ongoing concern. Herein, MnO 2 /Co–C catalyst layers were wrapped on SiO 2 nanofiber by a combination of thermal pyrolysis and redox reaction method to prepare catalytic membranes (MCCS-x) for the efficient purification of indoor PM and HCHO. The core-dual-shell structure maintains the pore structure of the membrane, providing high gas permeability of 670 m 3 ·m −2 ·h −1 ·kPa −1 . Owing to the introduction of MnO 2 /Co–C enhanced the capture of PM, the optimized MCCS-2 exhibits high filtration efficiency of PM 0.3 and PM 2.5 (99.60% and 99.99%) with a low pressure drop (<80 Pa). In addition, MCCS-2 achieves 100% HCHO removal efficiency at room temperature due to its large specific surface area, high redox property and abundant Mn 4+ and oxygen species. The appropriate proportion of Mn/Co bimetallic sites synergy inhibits the formation of formate and carbonate intermediate species, thus MCCS-2 possesses excellent long-term catalytic stability than contrast sample (MCCS-3 and MS). This work demonstrates a new approach for the fabrication of high-performance catalytic membrane materials for indoor air purification.
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