CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Baolu Shi,Zhiliang Zhou,Yu Chen,Xinqiao Wang,Baosheng Xu
SiO 2 aerogels have an inherent optical transparency, but there is a hydrophilic defect and high transparency and hydrophobicity seem impossible to achieve at the same time. In order to realize the practical application value of highly transparent aerogel, our study used hexamethyldisilazane (HMDS) as the hydrophobic agent to improve the hydrophobicity of the prepared highly transparent SiO 2 aerogels. We investigated the effects of HMDS concentration and modification duration on SiO 2 aerogels through the chemical liquid method. Results showed that the concentration and modification time of HMDS have no significant effect on the microstructure and properties of highly transparent SiO 2 aerogels, which maintained uniform microstructure, low thermal conductivity , good thermal stability and contact angles were all above 136°. Hydrophobic and highly transparent SiO 2 aerogels hold great potential for use as observation windows in the aerospace applications, building thermal management, and transparent coating.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2023
·Vol. 16
·期 6
·2292
·
IF 3.4
Zhixiang Zhu,Shengyuan Wang,Ya Zhong,Qi You,Jun Gao,Sheng Cui,Xiaodong Shen
Dye wastewater has caused great harm to the environment, which is an urgent problem to be solved. As typical three-dimensional porous materials, aerogels have attracted great interest in dye wastewater treatment. In this work, spherical attapulgite/silica (ATP/SiO2) gels were initially prepared by easily scalable sol-gel dripping methods and then dried to aerogels with three drying techniques, namely, supercritical CO2drying (SCD), freeze-drying (FD), and ambient pressure drying (APD). The effect of the drying techniques and heat-treated temperature on the physical characteristic, morphological properties, microstructure, and chemical structure of the spherical ATP/SiO2aerogels were investigated. The macroscopic morphology of the spherical ATP/SiO2aerogels was homogeneous and integrated without local cracking. The average pore diameter and specific surface area of the spherical ATP/SiO2aerogels prepared by the three drying techniques were in the range of 6.8–8.6 nm and 218.5–267.4 m2/g, respectively. The heat treatment temperature had a significant effect on the pore structure and the wetting properties of the aerogels. The 600 °C heat-treated aerogels were subjected to adsorption tests in methylene blue (MB) solution (60 mg/g, 100 mL), which exhibited a great adsorption capacity of 102.50 mg/g. Therefore, the resulting spherical ATP/SiO2aerogels possessed multipath preparation and exhibited an efficient adsorption performance, with the potential to be applied as an adsorbent for dye wastewater.Keywords:spherical ATP/SiO2aerogels;drying techniques;heat treatment;adsorption performance
研究领域:
环境科学
·
材料科学
·
废水处理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Gels
·
2023
·Vol. 9
·期 5
·405
·
IF 4.6
Feng Liu,Xin Di,Xiaohan Sun,Xin Wang,Tinghan Yang,Meng Wang,Jian Li,Chengyu Wang,Yudong Li
The persistent challenge of removing viscous oil on water surfaces continues to pose a major concern and requires immediate attention. Here, a novel solution has been introduced in the form of a superhydrophobic/superoleophilic PDMS/SiO2aerogel fabric gathering device (SFGD). The SFGD is based on the adhesive and kinematic viscosity properties of oil, enabling self-driven collection of floating oil on the water surface. The SFGD is able to spontaneously capture the floating oil, selectively filter it, and sustainably collect it into its porous fabric interior through the synergistic effects of surface tension, gravity, and liquid pressure. This eliminates the need for auxiliary operations such as pumping, pouring, or squeezing. The SFGD demonstrates exceptional average recovery efficiencies of 94% for oils with viscosities ranging from 10 to 1000 mPa·s at room temperature, including dimethylsilicone oil, soybean oil, and machine oil. With its facile design, ease of fabrication, high recovery efficiency, excellent reclaiming capabilities, and scalability for multiple oil mixtures, the SFGD represents a significant advancement in the separation of immiscible oil/water mixtures of various viscosities and brings the separation process one step closer to practical application.
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 NON-CRYSTALLINE SOLIDS
·
2025
·
IF 3.5
Wang Zhan,Jinhong Mo,Lingling Tang,Fan Shi,Le Chen,Lixia Li,Mingyi Chen,Qinghong Kong,Ru Zhou,Juncheng Jiang
Considering that the poor mechanical properties limit the application of SiO 2 aerogels in fire insulation, polyurethane sponges, and mica were used to enhance the mechanical properties of SiO 2 aerogels in this study. The effects of polyurethane sponges with different pore sizes and mica content on the thermal-mechanical properties of composite aerogels were investigated. The internal structure of the composite aerogels was analyzed by scanning electron microscopy. Moreover, the chemical structure and composition of the composite aerogels were characterized and analyzed. The results demonstrate that polyurethane sponges and mica can effectively enhance the mechanical properties of composite aerogels. However, the addition of mica increased the thermal conductivity. The experimental data will further expand the engineering application of SiO 2 aerogels.
研究领域:
材料科学
·
热能工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2024
·
IF 5.8
Yuhan Ren,Biao Zhang,Zhaoxin Zhong,Jian Ye,Jiawei Zhang,Zhiyong Fang,Feng Ye
In this study, monolithic Al 2 O 3 –SiO 2 aerogels with excellent thermal stability and high specific surface area were synthesized using boehmite nanorods (L=20–30 nm, D=3–5 nm). The high specific surface area of aerogels was maintained after calcination at 800 °C (663.54 m 2 /g), 1000 °C (486.91 m 2 /g), and 1100 °C (230.76 m 2 /g). The anti-sintering mechanism of the Al 2 O 3 -SiO 2 aerogels was discussed. Thanks to the composite of Al 2 O 3 -SiO 2 aerogel and mullite fibers, the disadvantages of brittleness and low strength of aerogel are overcome. The thermal conductivity of the composite is extremely low at 0.034 W/(m·K)-0.089 W/(m·K) (25 °C-1000 °C). Five muffle cycle back-temperature tests at 1000 °C and a butane blowtorch back-temperature test at 1350 °C also proved that the composites have excellent thermal insulation properties. Composites with excellent thermal insulation properties combined with lightweight, thinness, machinability, and good dielectric properties meet the need for high-temperature thermal insulating-wave transmitting integrated materials for hypersonic missile radomes.
研究领域:
材料科学
·
航空航天工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Coatings Technology and Research
·
2024
·Vol. 21
·期 4
·1499-1512
·
IF 2.3
He Jianjun,Yan Jingyi,Pu Min,Jie Jun,Luo Guangwu,Zeng Zijing,Duan Zihao,Huang Caiyuan
Ice on the surface of wind turbine blades may result in power production losses and unsafe operations. An effective technological solution to the ice issue is coating de-icing. This study first constructed SiO 2 aerogel/CNTs (carbon nanotube) coating with photothermal de-icing by incorporating photothermal nanoparticles into the created nanoporous structure. The coating structure examined by SEM and EDS analysis demonstrates that CNT particles can be well captured by the three-dimensional nanostructure of SiO 2 aerogel and form a stable symbiotic skeleton. After that, we examined how the quantity of CNT doping affected the coating's surface morphology and photothermal properties. The findings demonstrated that the C-6 coating made from 0.6% CNTs performed best. Utilizing the photothermal effect of CNTs, it exhibited a steady rate of temperature increase and reached the target temperature of 153.4°C in 561 s upon near-infrared light (808 nm) irradiation. According to the results of experiments testing the photothermal performance, mechanical/chemical stability, and applicability of the coating, the coating has the advantages of being lightweight, provides quick de-icing, high stability, and simple production. This study not only increases the viability of using coating de-icing technology on wind turbine blades but also offers creative solutions to scientific investigation in the area of coating de-icing.
研究领域:
材料科学
·
能源工程
·
环境科学
✓ 已验证
DOI
高影响因子
WATER AIR AND SOIL POLLUTION
·
2024
·Vol. 235
·期 10
·1-15
·
IF 3.8
Liu Xu,Kong Xiaomin,Wen Hao,Wang Yue,Wu Meili,Yin Hongwei,Qin Wei,Wang Manli,Pei Jun,Qu Miaoming
Coal gangue, a byproduct of coal mining with massive generation, presents a major challenge for resource utilization. In this study, SiO 2 aerogel was successfully fabricated from coal gangue, via a facile and cost-effective approach. The aerogel boasts an intricate network framework structure internally and functions as a mesoporous material with measurements of 154.5662 m 2 ·g −1 for specific surface area and 7.9557 nm for average pore size. Additionally, exploring the adsorption capabilities of SiO 2 aerogel concerning Pb(II) in wastewater, the research revealed insights. The results demonstrated that the maximum Pb(II) removal efficiency reached 94.09% under pH 6, aerogel dosage of 1.5 g·L⁻ 1 , and initial Pb(II) concentration of 80 mg·L⁻ 1 . The adsorption process followed the Langmuir isotherm model and pseudo-second-order kinetic model, suggesting a favorable and predominantly monomolecular layer chemisorption, and the intraparticle diffusion model suggests internal diffusion behavior during adsorption. The SiO 2 aerogel exhibited specific adsorption behavior towards Pb(II). This study offers a promising avenue for repurposing coal gangue while addressing the issue of Pb(II)-contaminated wastewater.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2023
·
IF 9.5
Le Xu,Wenxia Zhu,Zhiwei Chen,Dong Su
Polymer-reinforced SiO2 aerogel materials exhibit excellent thermal insulation, flame resistance, and mechanical properties; however, the poor thermal stability of organic components limits their application in high-temperature environments. Herein, a double-network MK/SiO2 aerogel was synthesized by direct copolymerization of a methyl-containing silicone resin (MK) and tetraethoxysilane (TEOS) under the cross-coupling of (3-aminopropyl) triethoxysilane (APTES) followed by an atmospheric drying method. The resulting MK/SiO2 aerogel, presenting a double-cross-linked MK and SiO2 network, shows a low density of 0.18 g/cm3, a high specific surface area of 716.6 m2/g, and a low thermal conductivity of 0.030 W/(m K). Especifically, the compressive strength of the MK/SiO2 aerogel (up to 3.24 MPa) is an order of magnitude higher than that of the pristine SiO2 aerogel (0.39 MPa) due to the introduction of the strong MK network and enhanced neck connections of SiO2 nanoparticles. Furthermore, the mutually supportive network endows the MK/SiO2 aerogels with significant resistance to ablation and oxidation up to 1000 °C, showing a high residual rate (89%), a high specific surface area (235.2 m2/g), and structural stability after thermal treatment under air atmosphere. These superior mechanical and thermal properties of the MK/SiO2 aerogels lead to attractive practical applications in energy transportation, thermal insulation, or aviation.
研究领域:
材料科学
·
热能工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Waste and Biomass Valorization
·
2024
·
IF 2.6
Wang Jiahe,Lu Jinshan,Wang Hongzhi
The reutilization of marble sludge from the marble cutting and polishing process offers economic and environmental benefits. In this work, fly ash is used as an aluminosilicate source to prepare geopolymers with marble sludge. The crystal composition, gel structure, pore distribution, microstructure and Na + ion leaching behavior were investigated to determine the effects of multiscale fillers on the apparent density, compressive strength, and efflorescence performance of the geopolymers. The addition of graphene oxide (GO) filler catalytically promotes geopolymerization reactions, inhibits microcrack formation and increases the compressive strength, albeit with pronounced efflorescence. In contrast, the hydrophobic SiO 2 aerogel (SA) filler effectively eliminates the pores and hinders water permeability and Na + leaching, thus greatly improving the anti-efflorescence properties. The concentration of Na + ions in the leach solution follows an exponential relationship with leach time, indicating diffusion controlled leaching behavior. With the combination of 1‰ GO and 1% SA, the geopolymer achieves a compressive strength of 40.6 MPa and a surface contact angle of 99.1°. After the immersion efflorescence test, the geopolymer shows a mass loss of 4.3% and a strength loss of 7.2%, far superior to those of the unfilled geopolymer. The strengthening and improved anti-efflorescence properties are closely related to the densification and increased hydrophobicity of the geopolymers. The synergistic effect of different fillers provides a simple technical route to produce high strength and anti-efflorescence geopolymers with marble sludge, promising suitability for applications in paving and embankment blocks. Graphical Abstract
研究领域:
材料科学
·
环境工程
✓ 已验证
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
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2020
·
IF 2.369
Yongkang Lu,Bo Zhang,Shaobo Liu,Luxia Yin,Wanghui Gong,Jianguang Gao,Zekai Zhang,Wensheng Ning
Pd/SiO2-n aerogel composites with different Si/Pd mole ratios (n(Si/Pd)) were synthesized by a sol–gel method followed by drying in the atmosphere to adsorb thiophenic compounds from model oils. For Pd/SiO2-n, doping Pd species in SiO2 aerogels led to the appearance of weak Lewis acidic sites on the surface. The adsorption capacity of Pd/SiO2-n was significantly higher than that of pure SiO2, owing to the π-complexation, S–M bonding, and acid–base interaction between Pd2+ and thiophenic compounds. Among them, the capacity of Pd/SiO2-318 was the highest, 4.76 mg S/gads (i.e., 9.37 μmol S/μmol Pd), which was obviously higher than that of sorbents reported such as Pd/activated carbon and Pd/Al2O3, based on the amount of thiophene adsorbed per unit active centers. In the presence of aromatics and olefins, the selectivity of Pd/SiO2 for thiophene was higher than that of Ag/SiO2 and Cu/SiO2 reported, attributed to the stronger S–Pd bonding than the S–Ag and S–Cu bonding. The equilibrium adsorption data of thiophene onto Pd/SiO2-318 were well simulated with the Langmuir and Freundlich models. Combined with thermodynamic results, it can be found that the low temperature was favorable for the adsorption of thiophene. Pd/SiO2 exhibited a good regeneration performance after solvent washing.
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 POROUS MATERIALS
·
2023
·Vol. 30
·期 5
·1753-1761
·
IF 2.6
Zhao Wenpu,Ji Yuecheng,Pang Yifan,Li Xiaolei,Ji Huiming
Al 2 O 3 -SiO 2 aerogel (ASA) was prepared by convenient ambient pressure drying using inexpensive AlCl 3 ·H 2 O as precursor, and silicon was deposited during the aging of aluminum gel. To explore the influence of Chloride ion on the property of ASA, ion exchange technology was used to remove the Chloride ion in the aluminum sol. ASA exhibits a low thermal conductivity of 0.029 W m −1 K −1 at room temperature, and the specific surface area of Cl-free ASA after heat-treated at 1200 °C is 95.2 m 2 /g, which is higher than that of the chlorine-containing aerogel (11.4 m 2 /g), showing enhanced thermal stability of ASA. Analysis of XRD and XPS indicate that the removal of chloride ions makes it more difficult for ASA to establish Al–O–Si groups during the aging process, so the γ-Al 2 O 3 and cristobalite phase do not transform to mullite phase at 1200 °C. Due to the better thermal stability of ASA, it has great potential for high-temperature applications in the fields of insulation, thermal protection materials, and building external wall thermal insulation.
研究领域:
材料科学
·
纳米技术
·
热工工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）