Materials Research Express
·
2020
·Vol. 7
·期 6
·065309
·
IF 1.929
Ran Zhou,Haihong Ma,Zhengfa Zhou,Weibing Xu,Fengmei Ren,Chunhui Li
SiO2 particles were modified by γ-aminopropyltriethoxy silane (KH550) and γ-(2,3-epoxypropoxy)propyltrimethoxy silane (KH560) in sequence to prepare SiO2 particles with silicone-methoxy groups on surface (SiO2-s-Si(OCH3)3). X-ray photoelectron spectroscopy (XPS) and thermal gravimetric analysis (TGA) were used to characterize the modified SiO2 particles. The SiO2-s-Si(OCH3)3 particles and tetramethoxysilane were used to co-cure hydroxyl silicone oil. The strong interfacial interactions between silicone rubber and fillers, which came from hydrolyzed SiO2-s-Si(OCH3)3 particles in situ reacting with hydroxyl silicone oil, had a great effect on the properties of composites. The mechanical properties, thermal conductivity, dielectric strength and volume resistivity of SiO2-s-Si(OCH3)3/silicone rubber composites were considerably higher than that of pristine SiO2/silicone rubber composites at the same content of SiO2, while the dielectric constant and dielectric loss tangent of SiO2-s-Si(OCH3)3/silicone rubber composites was lower than that of pristine SiO2/silicone rubber composites at the same content of SiO2.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2019
·
IF 7.015
Qiuyun Zhu,Xi Tang,Shasha Feng,Zhaoxiang Zhong,Jianfeng Yao,Zhong Yao
Severe air pollution causing by particulate matter and VOCs calls for multifunctional air purification media. Here, we report a novel bioinspired bead-on-string-like ZIF-8@SiO 2 composite nanofiber membrane, which has a synergistic promoting effect on particulate matter (PM) capture and gas pollutants adsorption. The flexible SiO 2 nanofiber membrane was fabricated by electrospinning, while zeolitic imidazolate framework-8 (ZIF-8) nanocrystals were grown on the nanofibers by controlling the crystallization by contra-diffusion. The resultant ZIF-8@SiO 2 composite membrane showed high removal efficiency of 99.96% for incense smoke which attributed to the ZIF-8 enhanced surface area and electrostatic interaction between beaded ZIF-8 nanocrystals and PM particles. Further, the uniformly loaded ZIF-8 nanocrystals with compatible pore size, large microporosity and specific surface area enhanced the formaldehyde adsorption efficiency to 79.53% in 2 h. The design of the ZIF-8@SiO 2 composite membrane with fascinating PM removal efficiency and excellent formaldehyde adsorption capacity would make it a promising medium for multicomponent air purification.
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
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2020
·Vol. 27
·期 11
·12017-12029
·
IF 3.056
Lv Yuancai,Huang Siyi,Huang Guofu,Liu Yifan,Yang Guifang,Lin Chunxiang,Xiao Gao,Wang Yonghao,Liu Minghua
Given their considerable solubility in water and potentially high toxicity to human health, organoarsenic compounds have become an emerging contaminant. Herein, a heterogeneous Fenton process mediated by SiO 2 -coated nano zero-valent iron (SiO 2 -nZVI) was employed to simultaneously remove the p -arsanilic acid ( p -ASA, a typical organoarsenic compound) and the released arsenic. The initial pH value significantly influenced on the degradation of p -ASA and at the optimal pH (3.0), p -ASA (10 mg L −1 ) could be completely oxidized to As(V), NH 4 + , and plentiful phenolic compounds such as phenol and p -hydroquinone via the cleavage of C–N and C–As bonds within 60 min in pure water. Meanwhile, although the formed lepidocrocite and magnetite on the surface of SiO 2 -nZVI significantly limited the reutilization, they played a vital role in the adsorption of the released As(V) and the residual arsenic levels in the effluent were as low as 0.031 mg L −1 , meeting both the drinking water standard of the World Health Organization (WHO) and the surface water standard of China (0.05 mg L −1 ). Furthermore, high-level dissolved organic matters (DOM) (> 2 mg C L −1 ) exhibited strong interference with both the oxidation of p -ASA and adsorption of arsenic, but the interference could be eliminated by increasing the SiO 2 -nZVI dosage or adding H 2 O 2 . Importantly, this system could completely remediate p -ASA in a short time and simultaneously avoid the secondary pollution caused by inorganic arsenic, which was significant for the remediation of organoarsenic pollutants in swine wastewater.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
LANGMUIR
·
2022
·
IF 4.331
Zihan Gu,Zhaomin Li,Zhengxiao Xu,Chao Zhang
In this paper, the microscopic mechanisms and macroscopic characteristics of polymer/nanoparticle foam flooding in a heavy oil reservoir environment were studied. Sodium dodecyl sulfate (SDS) surfactant was used as the foaming agent, and the foam was prepared by a combination of partially hydrolyzed polyacrylamide (HPAM) polymer and SiO2 nanoparticles. By performing experiments with the microscopic model, the foam flooding dynamics in the heavy oil reservoir were simulated. Based on the experiments, the formula model was established to evaluate the physicochemical effects between the foam liquid film and oil surface. Finally, the macroscopic characteristics of foam flooding were studied by performing oil displacement experiments with a 2D visual model. The microscopic experiments demonstrated that the foam liquid film could exert multiple actions, such as adsorption, stretching, and cutting on the heavy oil in the reservoir pores. These actions were accompanied by force changes between the foam and heavy oil, and the addition of polymer and nanoparticles further strengthened them. The calculations of the formula model indicated that the polymer and nanoparticles amplified the force between the foam liquid film and heavy oil by 1.95 and 2.2 times, respectively. The 2D visual model experiments suggested that foam flooding could further develop heavy oil after water flooding through its liquid film effects, and the oil recovery efficiency increased from 42.43 to 57.82%. In addition, the polymer and nanoparticles further optimized the oil displacement effect of the foam liquid film, which made the oil recovery efficiency reach 64.77–68.16%.
研究领域:
石油工程
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材料科学
·
表面化学
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2024
·
IF 8.4
Zhuoqun Li,Guangshun Dong,Jian Pan,Xinyu Chen,Xinyu Lou,Lilan Huang,Kai Guo
With the continuous development of environmental protection and resource recycling demands, the development of bio-based separation membrane materials has increasingly attracted attention. Bio-based polyamide 56 (PA56), exhibiting excellent hydrophilicity, spinnability, and mechanical properties, is expected to complement and replace traditional separation membrane materials. In this study, the electrospinning preparation and structural control of PA56 nanofiber membranes were achieved through the optimization of PA56 content and mixed solvent ratios. The study found that when the PA56 content was 16 wt% and the formic acid to acetone ratio in the mixed solvent was 8:2, the nanofiber diameter distribution was the most uniform. Building on this, amino-functionalized modified silica (SiO 2 –NH 2 ) nanoparticles were introduced to prepare PA56/SiO 2 –NH 2 composite nanofiber membranes featuring a cobweb-like nanofiber network and micro-nodule structure. The effects of the addition of SiO 2 –NH 2 nanoparticles on the morphology, structure, and properties of the fiber membranes were studied. The results indicate that the control of the mixed solvent ratio and the addition of SiO 2 –NH 2 nanoparticles led to the formation of a cobweb-like nanofiber network and micro-nano nodular structure on the nanofiber surface, enhancing the hydrophilicity of PA56 nanofiber membranes. The M − 3 membrane with a nanoparticle addition amount of 0.8 wt% exhibited high hydrophilicity and underwater superoleophobic properties, achieving efficient separation of stable oil-in-water emulsions with a separation efficiency of 99.8 %. This work provides a new bio-based membrane material and its preparation method for treating oily wastewater using the membrane separation method.
研究领域:
材料科学
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环境科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry B
·
2020
·Vol. 8
·期 26
·5707-5721
·
IF 5.344
Mingdi Sun,Dan Yang,Wu Fanqi,Zhao Wang,Hongjiao Ji,Zhiliang Liu,Shili Gai,Fangmei Zhang,Piaoping Yang
Photodynamic therapy (PDT) is a light-based modality for tumor treatment that involves the generation of reactive oxygen species (ROS) by the combination of light, a photosensitizer, and molecular oxygen. Nevertheless, the therapeutic effects of PDT are limited by hypoxic conditions that worsen with oxygen consumption during the PDT process. Photo/chemodynamic therapy (PCDT) based on the Fenton reaction is one strategy to improve ROS generation, provided a highly effective Fenton reagent is developed. In this research, SiO2@Cu7S4 nanotubes (NTs) were synthesized as a PCDT agent. This double-valence metal-sulfide composite material can react with H2O2 at the tumor site. SiO2@Cu7S4 NTs can produce more ROS than the traditional PDT agents, and besides, they can also be used as a photothermal therapy (PTT) agent. SiO2@Cu7S4 NTs will trigger the PTT effect under 808 nm irradiation and generate a large amount of heat to eradicate cancer cells. This heat will also promote the PCDT effect by increasing the reaction rate. Thus, the SiO2@Cu7S4 NT is a suitable material for PCDT and PTT synergistic oncotherapy. The 808 nm laser is selected as the appropriate excitation source, providing adequate penetration and minimal harm to normal cells. The experimental data presented herein demonstrate the promising photosensitive, Fenton-like, and photothermal performance of SiO2@Cu7S4 NTs. Furthermore, the findings could promote the development of PCDT and PTT synergistic therapy. Thus, this research provides a feasible method to design a single, multifunctional material for cancer treatment.
研究领域:
肿瘤学
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材料科学
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纳米医学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2016
·
IF 8.328
Jing Hu,Haiqiang Wang,Fan Dong,Zhongbiao Wu
Photothermal effect was for the first time utilized to capture the energy from infrared light and to promote the photocatalytic oxidation activity of NO by a simply mechanical mixing of traditional photocatalysts and core-shell structured Fe 3 O 4 @SiO 2 . Fe 3 O 4 @SiO 2 absorbed the infrared light, transferred it into thermal energy based on photothermal effect, which then accelerated the NO photocatalytic activity of traditional photocatalysts. This promotion effect led by the addition of Fe 3 O 4 @SiO 2 was confirmed by several classical photocatalysts such as TiO 2 , g-C 3 N 4 , BiOI and CeO 2 . To quantitatively characterize the photothermal effect, thermo images were taken with a thermo imager to obtain the average temperature rise of samples under the illumination of simulated solar light. Specially, P25/Fe 3 O 4 @SiO 2 was studied in depth for illustration of the promotion mechanism. Experimental results showed that with the contribution of SiO 2 shell, the photocorrosion of Fe 3 O 4 didn’t occur during photocatalytic oxidation process and the photothermal effect of Fe 3 O 4 was maintained. The quantity of Fe 3 O 4 @SiO 2 was a vital factor for promotion of photocatalytic activity and the optimum mass ratio of P25 and Fe 3 O 4 @SiO 2 was 3–1. After 120 min of illumination, the temperature of optimum P25/Fe 3 O 4 @SiO 2 rose to 57.4 °C from 25 °C and its NO conversion capability showed an enhancement of 38.9% with the comparison to pure P25. The experimental results confirmed that the rise of temperature was attributed to the photothermal effect and its contribution was the same as the directly heating of photocatalysts. Furthermore, the enhancement of NO conversion capability around 30–40% was observed for the Fe 3 O 4 @SiO 2 mixed anatase TiO 2 , g-C 3 N 4 , ZnO, BiOI and CeO 2 . In sum, we developed a new strategy for utilization of NIR light of solar energy to facilitate the photocatalytic reactions.
研究领域:
环境科学
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材料科学
·
光催化
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Li Li,Xinhong Chen,Xia Xiong,Xiaoping Wu,Zinan Xie,Zuohua Liu
The development of a simple and environmentally friendly method to synthesize hollow TiO 2 structures is urgent for realizing high NIR reflectance and low thermal conductivity . Hollow TiO 2 @SiO 2 structures have been successfully synthesized by a recycling template method. The synthesis process involves four steps as follows: 1) preparation of SiO 2 spheres, 2) synthesis of SiO 2 @TiO 2 core-shell structure by coating mesoporous TiO 2 shell on SiO 2 and crystallization by calcination , 3) etching the SiO 2 @TiO 2 to form the hollow TiO 2 spheres, and 4) coating the hollow TiO 2 spheres with a SiO 2 protection layer to produce hollow TiO 2 @SiO 2 structures. The SiO 2 serves as a template to support and synthesize hollow TiO 2 shell, and then after being etched, to form a Na 2 SiO 3 solution as a coating agent to protect TiO 2 shell from photocatalytic activity. The as-synthesized hollow TiO 2 @SiO 2 structures not only have high NIR reflectance, but also have a high thermal barrier performance due to the hollow structure. Moreover, the NIR reflectance of the coating made from hollow TiO 2 @SiO 2 reached 94.9%, and the temperature of the inner surface of the coating board is reduced about 16 °C, compared with the surface without coating. The weather resistance studies reveal that the hollow TiO 2 @SiO 2 sample is very stable under the UV irradiation. In particular, the hollow TiO 2 @SiO 2 structures synthesized by using this method shows multifunctional responses towards solar heat.
研究领域:
材料科学
·
纳米技术
✓ 已验证
DOI
高影响因子
COMPOSITES PART B-ENGINEERING
·
2025
·
IF 14.2
Chuanyi Liu,Wenlong Xu,Cheng Wang,Dong Ma,Zhihui Zeng,Na Wu
In industrial explosion accidents, mechanical shock waves and flame thermal radiation are the main destructive factors, posing serious threat to life and property. Current designs mainly focus on one of these factors, so it is necessary to develop protective materials against both destructive factors. TPP (Triphenyl phosphate) - SiO 2 Aerogel synergistically modified polyurea composites were developed in this work, which process excellent mechanical shock wave mitigation performance and enhanced flame retardancy. The mechanical shock wave mitigation experiments were conducted on Multi-purpose Shock Cannon (MSC), Human Tissue Equivalent Target (HTET) and full-scale human head model, which comprehensively evaluated the protective performance of polyurea composites for the human body. The flame retardancy was assessed through thermal conductivity, LOI, thermal gravimetric and small flame experiment. The combustion residue was analyzed using SEM, EDS, Raman spectroscopy, and XPS technologies, revealing flame retardant mechanism of TPP-SiO 2 Aerogel synergistically modified polyurea composites. The results showed that the TPP-SiO 2 Aerogel synergistically modified polyurea composites achieved the highest mitigation ratios of overpressure peak and acceleration peak at 13.20% and 60.87%, respectively, superior to those of fiber-enhanced polymer composites (Fiber-PE, Fiber-PA6, Fiber-ASA), single filler polyurea, wood and PLA plastic. The flame retardancy was effectively improved, with the highest LOI reaching 24.9%, far higher than that of pure polyurea (19.6%). It particularly enhanced the carbonization performance of polyurea composites during combustion, eliminating burning material dropping phenomenon. The thermal insulation performance was also elevated, with the lowest thermal conductivity reduced by 58.6% compared to pure polyurea.
研究领域:
材料科学
·
安全工程
·
燃烧学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2024
·Vol. 107
·期 9
·6422-6438
·
IF 3.5
Wenjun Yu,Zihua Lei,Xiaoyu Zhang,Qinzhao Zhang,Yongxing Cheng,Ying Deng,Yang Li,Junjie Song,Le Fu
Ceramics can be traditionally classified as structural and functional ones. However, the miniaturization and multi-functionalization of various devices require ceramics to have both structural and functional properties. In this work, we aimed to develop structure-function integrated ZrO 2 –SiO 2 nanocrystalline glass–ceramics (NCGCs) by in situ formation of homogenously distributed amorphous carbon. By reducing the calcination temperature of carbon-containing powder, organic carbon groups were partially retained in the powder and they transformed to amorphous carbon in the sintered NCGCs. At micrometer scale, the carbon was homogenously distributed in the NCGCs, avoiding the commonly encountered agglomeration problem of carbon fillers. The effects of carbon on the microstructure, mechanical properties, wear resistance, and dielectric properties of the NCGCs were investigated. Results showed that the in situ formed amorphous carbon was homogenously distributed in the ZrO 2 nanocrystallites. Meanwhile, the amorphous carbon strongly bonded with the ZrO 2 –SiO 2 NCGCs. Only a small amount of carbon was combusted even after annealing at 1000°C for 3 h. The formation of amorphous carbon led to an improvement of nanohardness and wear resistance of the NCGCs, while slightly reducing Young's modulus and flexural strength. The electromagnetic wave transmission performances were improved due to the formation of amorphous carbon. The current study paves a new way for developing structure-function integrated glass–ceramics through in situ formation of carbon. The prepared structure-function integrated ZrO 2 –SiO 2 NCGCs have great potential to be used as radome and antenna windows of aerospace aircrafts that work in harsh environment.
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
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
·
2022
·Vol. 61
·期 18
·e202117201
·
IF 16.823
Jiaqi Si,Guofeng Zhao,Weidong Sun,Jincun Liu,Cairu Guan,Yong Yang,Xue-Rong Shi,Yong Lu
Graphical For the oxidative coupling of methane (OCM) reaction, the MnO x -Na 2 WO 4 /SiO 2 catalyst enriched with Q 2 units in the SiO 2 carrier achieves 23 % CH 4 conversion and 72 % C 2–3 selectivity at 660 °C. A large number of Q 2 units in MnO x -Na 2 WO 4 /SiO 2 is a trigger for markedly lowering the light-off temperature of the Mn 3+ ↔Mn 2+ redox cycle because of the easy formation of MnSiO 3 . Oxidative coupling of methane (OCM) catalyzed by MnO x -Na 2 WO 4 /SiO 2 has great industrial promise to convert methane directly to C 2–3 products, but its high light-off temperature is the most challenging obstacle to commercialization and its working mechanism is still a mystery. We report the discovery of a low-temperature active and selective MnO x -Na 2 WO 4 /SiO 2 catalyst enriched with Q 2 units in the SiO 2 carrier, being capable of converting 23 % CH 4 with 72 % C 2–3 selectivity at 660 °C. From experiments and theoretical calculations, a large number of Q 2 units in the MnO x -Na 2 WO 4 /SiO 2 catalyst is a trigger for markedly lowering the light-off temperature of the Mn 3+ ↔Mn 2+ redox cycle involved in the OCM reaction because of the easy formation of MnSiO 3 . Notably, the MnSiO 3 formation proceeds merely through the SiO 2 -involved reaction in the presence of Na 2 WO 4 : Mn 7 SiO 12 +6 SiO 2 ↔7 MnSiO 3 +1.5 O 2 . The Na 2 WO 4 not only drives the light-off of this cycle but also gets it working with substantial selectivity toward C 2–3 products. Our findings shine a light on the rational design of more advanced MnO x -Na 2 WO 4 based OCM catalysts through establishing new Mn 3+ ↔Mn 2+ redox cycles with lowered light-off temperature.
研究领域:
催化化学
·
材料科学
·
能源化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2016
·
IF 3.299
Haiye Wang,Xinzhen Zhao,Chunju He
The polydimethylsiloxane modified silica (SiO 2 -g-PDMS) nanoparticles with hydrophilic core and hydrophobic shell are employed for the hybridization modification of PVDF ultrafiltration membrane to improve the separation and antifouling performances. The results suggest the modified SiO 2 -g-PDMS nanoparticles exhibit improved dispersion and significant amphiphilic characteristics, and the wetting properties of membrane surface and mimetic matrix of hybrid PVDF membranes are distinctly different with the contact angle values at 105° and 15°, respectively. In addition, the added SiO 2 -g-PDMS nanoparticles significantly improve the fouling repulsion and fouling release properties of hybrid PVDF membranes, the anti-adsorption ability and water flux recovery ratio (FRR-W) of hybrid PVDF membranes to the two typical pollutants of bovine serum albumin (BSA) and humic acid (HA) have been significantly improved. This article aims to provide a simple way to improve the antifouling performance of PVDF ultrafiltration membrane with dual-mode multi-functional modifier.
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