ChemistrySelect
·
2023
·Vol. 8
·期 47
·e202303036
·
IF 2.1
Nan Liu,Binglian Zhu,Rutong Zhang,Weiqiao Zhong,Qibin Chen
Graphical NH 2 -silica-C 8 H 17 nanosheets containing short n-octyl chains and aminopropyl groups were investigated as a novel toughening agent for enhancing the toughness and strength of epoxy resin. The incorporation of 0.5 wt.% Janus nanosheets led to remarkable enhancements in the mechanical, dynamic mechanical, and thermal properties of the epoxy resin, as evidenced by the characterization results. In this work, a NH 2 -silica-C 8 H 17 Janus nanosheet with short n -octyl chains on one side and aminopropyl groups on the opposite side was prepared by the sol-gel method. This nanosheet was used to improve the toughness and strength of epoxy resin. The morphologies and structures of Janus nanosheets and the properties of NH 2 -silica-C 8 H 17 /epoxy nanocomposites were characterized. Results show that the addition of Janus nanosheets not only increases the storage modulus and glass transition temperature of nanocomposites, but also improves their mechanical performance and thermal stability. The tensile strength, elongation at break, fracture toughness and impact strength of nanocomposites are increased by ca. 57, 80, 74 and 63 %, respectively, at the 0.5 wt.% loading of Janus nanosheets. These findings suggest that NH 2 -silica-C 8 H 17 Janus nanosheets exert an effective influence on the toughness and strength of ultimate nanocomposites, which is attributed to the fact that NH 2 -silica-C 8 H 17 Janus nanosheet simultaneously contains n -octyl and aminopropyl groups on both sides, thus improving the nanosheet/matrix interface adhesion.
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
EUROPEAN POLYMER JOURNAL
·
2021
·
IF 4.598
Mengnan Li,Xiuli Li,Chunyu Li,Hongchen Liu,Wenxiang Wang,Liangjiu Bai,Hou Chen,Lixia Yang
As functional nanocomposites, Janus nanomaterials can play an important role due to their asymmetric structure and different components on the same surface. In this manuscript, hollow silicon spheres (SiO 2 JHs) with an asymmetric structure were prepared by an emulsion interfacial self-organized sol-gel process. Inspired by mussel chemistry, the exposed surfaces of the SiO 2 JHs were modified chemically by polydopamine (PDA). 2-(3-(6-Methyl-4-oxo-1,2,3,4-tetrahydropyrimidin-2-yl)ureido)ethyl methacrylate (MAUPy) containing multiple hydrogen bond groups were grafted to obtain SiO 2 @PDA/PMAUPy Janus Nanosheets (SiO 2 @PDA/PMAUPy JNs) by Pickering emulsion. The prepared SiO 2 @PDA/PMAUPy JNs were further applied to prepare nanocomposite self-healing hydrogels. As a result of the synergy of reversible non-covalent metal-ligand and hydrogen bonding, hydrogels with dual self-healing feature were successfully fabricated. The obtained hydrogels maintain preferable mechanical properties (strain of about 411.0% and stress of about 4.1 MPa) and excellent healing ratio (92.6%), which may have broad application prospects in smart flexible sensor and biomedical application.
研究领域:
材料科学
·
生物医学工程
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DOI
高影响因子
JOURNAL OF CATALYSIS
·
2021
·
IF 7.92
Chaoping Li,Su Liu,Yibing Pi,Jingwen Feng,Zewei Liu,Shiye Li,Rong Tan
High oil/water interfacial area together with accessible interfaces for regents is the key to achieving efficient asymmetric catalysis in water. Herein, by taking advantage of the excellent interfacial activity of Janus nanosheets (JNS), as well as the unique compatibility of imidazolium ionic liquid (IL), we developed a series of IL -functionalized amphiphilic Janus mesosilica nanosheets which afford highly accessible reaction interfaces for highly enantioselective sulfoxidation in water. The JNS-typed chiral salen Ti IV catalysts were prepared by selectively decorating hydrophobic chiral salen Ti IV complex on one side of Janus mesosilica nanosheets through the imidazolium-based IL linker. Benefiting from the two-dimensional porous Janus structure, as well as the compatible IL linker, the IL -tagged JNS catalysts afforded high oil/water interfacial areas and highly accessible reaction interface for sulfides and H 2 O 2 , significantly accelerating asymmetric sulfoxidation in water using H 2 O 2 as an oxidant. In addition, they can be facilely recovered for stable reuse by simple centrifugation.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2023
·
IF 6.6
Yan Fang,Zhe Chen,Chongyi Chi,Qinhui Chen
Defects in the curing process of epoxy coatings tend to deteriorate the anticorrosion performance of the coatings. An important way to enhance the anticorrosion performance of epoxy coatings is to add flaky fillers. In this paper, anisotropic Janus nanosheets (JNs) were prepared and modified by cardanol (CA) and Zn 2+ . Then, the obtained CA@JNs@Zn 2+ Janus composite nanosheets were introduced into epoxy coatings. When the content of CA@JNs@Zn 2+ is 0.2 %, the mechanical properties and corrosion resistance of the coating were effectively improved. The tensile strength of 0.2 %-CA@JNs@Zn 2+ /EP coating is 79 % higher than that of pure epoxy coating. The EIS analysis showed that the low-frequency impedance of the coating remained as high as 16.45 Gohm·cm 2 after 35 days of immersion, and remained above 10 Gohm·cm 2 during the whole immersion period, which demonstrating the optimal corrosion resistance. This paper provides a theoretical basis for the preliminary application of Janus material in the field of anticorrosion, and the prepared composite coatings are expected to be used for anticorrosion in harsh environment.
研究领域:
材料科学
·
防腐蚀工程
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2020
·
IF 3.99
Ming Han,Hong-Guo Liu
Two-dimensional (2D) Janus nanostructures have attracted much interest due to their unique structure and properties, and researchers are making great efforts continuously to explore new preparation methods. Herein, we reported a facile method to fabricate Janus nanosheets with lamellar structures at the air/liquid interface of a water-miscible organic solution of fatty acids and an aqueous solution of metal ions . The organic solution spread on the subphase surface and diffuse into the subphase simultaneously, and the aqueous solution diffused into the organic solution at the same time. Thus, the fatty acid molecules and metal ions self-assembled into layered nanosheets with the aid of hydrophobic interaction of alkyl chains and coordination between carboxylic groups and metal ions in the mixed solution. The sides facing to air and the subphase are composed of alkyl chains and carboxylates, respectively, indicating that the nanosheets are Janus ones. Various organic solvents , metal ions and fatty acid molecules have been tried to fabricate such layered Janus nanosheets. This method is expected to be a useful way to assemble Janus nanostructures.
研究领域:
材料科学
·
纳米技术
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产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2021
·
IF 8.128
Heng Yu,Zheng Zheng,Bintao Hu,Zhangfan Ye,Xiaomin Zhu,Yongliang Zhao,Haitao Wang
Hypothesis Janus nanosheets , which have two surfaces of different functionalities, exhibit unique interfacial properties . In this work, we propose a facile and scalable technique for preparation of silica-based Janus nanosheets, which is based on formation of high internal phase water-in-oil emulsions stabilized solely by alkyl-substituted polyethoxysiloxanes due to their hydrolysis-induced interfacial activity. Experiments Janus nanosheets are then obtained by crushing the silica foams converted from such emulsions. The morphology of Janus nanosheets is investigated by field-emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). The chemical structure of functional silica materials is characterized by Fourier transform infrared spectroscopy (FT-IR). The asymmetric structure of silica nanosheets is observed by confocal laser scanning microscopy . Findings The resulting nanosheets have a rough hydrophobic surface and a smooth hydrophilic one, and are capable of stabilizing Pickering oil-in-water emulsions. Remarkably, pH-responsiveness of emulsions can be attained using the nanosheets whose hydrophilic surface is substituted with amino groups. Fast oil–water separation is achieved by the Janus nanosheets, which has been demonstrated by the nanosheets with a polystyrene-coated hydrophobic surface. This work paves a new avenue for large-scale production of functional silica-based Janus nanosheets suitable for numerous promising applications.
研究领域:
材料科学
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化学工程
·
界面化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Environmental Science-Nano
·
2023
·
IF 7.3
Haosen Zhao,Xin Hu,Hu Kang,Dongdong Yang,Mutai Bao,Yiming Li
Marine oil spills cause significant pollution to the global environment. Dispersants are frequently used in such spills to break down the oil slick into smaller droplets, facilitating the biodegradation of the oil. Herein, Janus nanosheets (JNs) were used as a new particulate dispersant, which could act synergistically with bacteria in seawater to remediate marine oil spill pollution efficiently. The JNs not only possessed amphiphilic properties and low toxicity but also demonstrated exceptional emulsification capabilities for oil, synergistically enhancing the remediation process alongside oil-degrading bacteria. Due to the inherent constraints on interfacial rotation and multilayer steric hindrance at the diesel–water interface, the emulsion created by JNs remained highly stable, maintaining a small oil droplet size even after a month. Significantly, the JNs enabled the binding of negatively charged oil-degrading bacteria through electrostatic interactions. Following their combination, the JNs effectively transported bacteria directly to the surface of the oil droplets through the influence of sea waves. This cooperative treatment system not only enhanced the oil's dispersibility but also markedly augmented the biodegradation of the oil when compared to the use of bacteria alone. At a diesel concentration of 6 mL L−1 and a JN concentration of 0.3 g L−1, the bacterial biodegradation of diesel was reduced from 5 days to 3 days, and the diesel biodegradation rate increased from 70% to 85%. These findings underscore the remarkable capacity of JNs to effectively emulsify oil and enhance bacterial oil degradation in seawater.
研究领域:
环境科学
·
微生物学
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产品关联
DOI
高影响因子
Polymers
·
2023
·Vol. 15
·期 11
·2515
·
IF 5
Yixuan Mao,Alain Luigi Lanzon,Botuo Zheng,Zhengxiao Xu,Jiatong Jiang,David Harbottle,Kai Yu,Mingfeng Chen,Yu Sheng,Huagui Zhang
To meet the increasing global demand for energy, better recovery of crude oil from reservoirs must be achieved using methods that are economical and environmentally benign. Here, we have developed a nanofluid of amphiphilic clay-based Janus nanosheets via a facile and scalable method that provides potential to enhance oil recovery. With the aid of dimethyl sulfoxide (DMSO) intercalation and ultrasonication, kaolinite was exfoliated into nanosheets (KaolNS) before being grafted with 3-methacryloxypropyl-triemethoxysilane (KH570) on the Alumina Octahedral Sheet at 40 and 70 °C to form amphiphilic Janus nanosheets (i.e., KaolKH@40 and KaolKH@70). The amphiphilicity and Janus nature of the KaolKH nanosheets have been well demonstrated, with distinct wettability obtained on two sides of the nanosheets, and the KaolKH@70 was more amphiphilic than the KaolKH@40. Upon preparing Pickering emulsion in a hydrophilic glass tube, the KaolKH@40 preferentially stabilized emulsions, while the KaolNS and KaolKH@70 tended to form an observable and high-strength elastic planar interfacial film at the oil–water interface as well as films climbing along the tube’s surface, which were supposed to be the result of emulsion instability and the strong adherence of Janus nanosheets towards tube’s surface. Subsequently, the KaolKH was grafted with poly(N-Isopropylacrylamide) (PNIPAAm), and the prepared thermo-responsive Janus nanosheets demonstrated a reversible transformation between stable emulsion and the observable interfacial films. Finally, when the samples were subjected to core flooding tests, the nanofluid containing 0.01 wt% KaolKH@40 that formed stable emulsions showed an enhanced oil recovery (EOR) rate of 22.37%, outperforming the other nanofluids that formed observable films (an EOR rate ~13%), showcasing the superiority of Pickering emulsions from interfacial films. This work demonstrates that KH-570-modified amphiphilic clay-based Janus nanosheets have the potential to be used to improve oil recovery, especially when it is able to form stable Pickering emulsions.Keywords:nanofluid;Janus nanosheets;clay;enhanced oil recovery;rheology;poly(N-Isopropylacrylamide)
研究领域:
石油工程
·
材料科学
·
胶体化学
✓ 已验证
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2022
·
IF 5.518
Jipeng Guan,Yaru Yang,Bolin Tang,Xiaojun Shen,Yongjin Li
The non-spherical Janus nanosheets (JNSs) have been large-scale synthesized by grafting polystyrene (PS) chains and epoxy group on the opposite sides of JNS, denoted as epoxy-silica-PS JNS. The functional JNSs are employed as compatibilizer in the immiscible polyamide 6 (PA6)/polystyrene (PS) blend. In the melt-blending process, the JNS with epoxy group can react with carboxyl (amino)-capped PA6 and in-situ form the PA6-silica-PS JNS. Owing to the amphiphilicity and Pickering effect, the JNSs can be exclusively located at the polymeric interface and assemble into the nanosilica monolayer at 0.5 wt% loading. With increasing the JNSs loading, the size of dispersed PS phase is decreased gradually and the JNSs still maintain the single layer structure at the interface. The dynamic moduli of the blends have been effectively improved for the JNSs at the interface. This report provides an extended application of Janus nanosheets to stabilize and functionalize the polymeric interface.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
Petroleum Science
·
2024
·
IF 6
Hai-Rong Wu,Geng-Lin Li,Guo-Rui Xu,Jia-Wei Chang,Kun-Peng Hou,Wen-Hao Shao,Ji-Rui Hou
Inadequate strength and stability of active crude oil emulsions stabilized by conventional surfactants always lead to a limited plugging rate of plugging agents. Thus, to address this issue, the synthesis of amphiphilic Janus nanosheets was effectively carried out for enhancing the system performances and subsequently characterized. Based on the outcomes of orthogonal tests, an assessment was conducted on the nanosheet and surfactant formulations to optimize the enhancement of emulsion properties. The experimental demonstration of the complex system has revealed its remarkable emulsifying capability, ability to decrease interfacial tension and improve rheological behavior at high temperature (80 °C) and high salinity (35,000 ppm) conditions. Involving probable mechanism of the system performance enhancement is elucidated by considering the synergistic effect between surfactants and nanosheets. Furthermore, variables including water-to-oil ratio, salinity, temperature and stirring intensity during operation, which affect the properties of prepared emulsions, were investigated in detail. The efficacy and stability of the complex system in obstructing medium and high permeability cores were demonstrated. Notably, the core with a high permeability of 913.58 mD exhibited a plugging rate of 98.55%. This study establishes the foundations of medium and high permeability reservoirs plugging with novel active crude oil plugging agents in severe environments.
研究领域:
石油工程
·
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2022
·
IF 9.965
Yaqi Chen,Linrong Zhang,Jin Wang,Huixiang Sheng,Kaili Wang,Junjie Wang,Shunhao He,Liuyingzi Yu,Gang Lu
Interface/emulsion catalysis is an effective approach for many organic and inorganic chemical reactions. Positioning catalysts at the interface is essential for highly efficient interface/emulsion catalysis. The sheet-like Janus nanostructures may have great advantages in stabilizing emulsions and improving reaction efficiency. In this work, by using a simple emulsion reaction and photodeposition, we successfully prepare the Janus nanosheets with opposite sides composed of AuNPs/PdNPs and reduced graphene oxide (rGO) respectively, referred to as AuNP-rGO/PdNP-rGO Janus nanosheets . Due to the distinct hydrophilicities on opposite sides, the prepared Janus nanosheets demonstrate high efficiency in emulsion stabilization and emulsion catalysis. By introducing the prepared PdNP-rGO and AuNP-rGO Janus nanosheets in emulsion reactions, highly efficient hydrogenation of p -nitroanisole and photocatalytic degradation of Nile red are demonstrated. This work provides a simple and cost-effective method to prepare Janus nanosheets and realize highly efficient emulsion reactions, and this strategy can be extended to promote many other interface/emulsion reactions.
研究领域:
材料科学
·
催化化学
✓ 已验证
DOI
高影响因子
MACROMOLECULES
·
2018
·
IF 5.914
Huarong Nie,Xincheng Liang,Aihua He
Janus particles are promising for self-assembly at the liquid/liquid interface due to coexistence of the Pickering effect and the different wettability of both sides. In this study, we synthesize a Janus nanosheet and evaluate its ability to trap nonequilibrium morphology by interfacial self-assembly. The Janus nanosheet was synthesized by selectively grafting polymer chains, polystyrene (PS) or polyisoprene (PI), on each side of a silica nanosheet. The selective grafting method endow the nanosheet with two different wettabilities, which make it ideal for self-assembly and further jamming at the PS/PI interface. The interfacial jamming of the nanosheet trapped the intermediate, nonequilibrium morphology during phase separation of the polymer blends. Compared to other Janus materials, the Janus nanosheet has higher interfacial activity and reduces the free energy of the system more effectively due to its 2D structure. Only 2 wt % of Janus nanosheet is required to break the threshold and reach the jammed state. The Janus nanosheet is easily scaled up and has potential as a compatibilizer in polymer materials.
研究领域:
材料科学
·
高分子化学
✓ 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）