PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2017
·Vol. 19
·期 5
·3837-3844
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IF 4.123
Feifei Jia,Xian Zhang,Shaoxian Song
The adsorption of Hg2+ on natural molybdenum disulfide has been studied using atomic force microscope (AFM). The AFM imaging clearly illustrated the adsorption of Hg2+ on the surface of molybdenum disulfide, and also hydration layers on the surfaces. It was found that the presence of a hydration layer on molybdenum disulfide surfaces hindered the Hg2+ adsorption. Also, it was observed that the Hg2+ adsorbed appeared in the form of multilayers. The first adsorbed Hg2+ layer might be mainly attributed to the complexation of Hg2+ with S atoms exposed on molybdenum disulfide surfaces, while the second one might be due to the electrostatic interaction between negatively charged molybdenum disulfide and the cation Hg2+.
研究领域:
环境科学
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材料科学
·
表面化学
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产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 50
·40126-40134
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IF 3.84
Junao Zhu,Yanlei Su,Xueting Zhao,Yafei Li,Runnan Zhang,Xiaochen Fan,Yanyan Ma,Yuan Liu,Zhongyi Jiang
Zwitterions bearing balanced charge groups have attracted increasing attention to fabricate antifouling membranes due to their highly hydrated structure. The simple and efficient method of covalent connection to enhance the stability of the zwitterions on membrane surfaces is still challenging. Herein, s branched polyethyleneimine (PEI) was employed to synthesize the zwitterion by a quaternary amination reaction with sodium chloroacetate. A novel zwitterionic surface with neutral surface charge was constructed by grafting the PEI-based zwitterion (Z-PEI) onto the hydrolyzed PAN (H-PAN) membrane surface. Covalent bonds were formed between the Z-PEI and H-PAN membrane while the electrostatic attraction would promote this reaction. The zwitterionic membranes exhibited superior antifouling ability (flux recovery ratio of about 99.8% and total flux decline of about 31.4%) due to the formation of a tight hydration layer by zwitterions on the membrane surface. Furthermore, the flux recovery ratio was not changed obviously during the long term experiment and could be maintained at as high as 96.3 and 98.4% after immersion in acid and alkali solution, respectively. These results demonstrated that the long term and chemical stability of zwitterionic functional surfaces were significantly enhanced via multisite covalent anchorage.
研究领域:
材料科学
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膜技术
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表面工程
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高分子化学
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分离科学
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DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2024
·
IF 12.2
Xinchun Lu,Liguo Shen,Hongjun Lin,Lei Han,Jiarong Du,Cheng Chen,Jiaheng Teng,Bisheng Li,Wei Yu,Yanchao Xu
Efficient oil-water separation has always been a research hotspot in the field of environmental studies. Employing a one-step hydrothermal approach, NiFe-layered double hydroxides (LDH) nanosheets were synthesized on nickel foam substrates. The resulting NiFe-LDH/NF membrane exhibited rejection rates exceeding 99% across six diverse oil-water mixtures, concurrently demonstrating a remarkable ultra-high flux of 1.4 × 10 6 L·m −2 ·h −1 . This flux value significantly surpasses those documented in existing literature, maintaining stable performance over 1000 manual filtration cycles. These breakthroughs stem from the synergistic interplay among the three-dimensional channels of the nickel foam, the nanosheets, and the hydration layer. By leveraging the pore size of the foam to enhance the functionality of the hydration layer, the conventional trade-off between permeability and selectivity was transformed into a balanced force relationship between the hydration layer and the oil phase. The operational and failure mechanisms of the hydration layer were examined using the prepared NiFe-LDH/NF membrane, validating the correlation between oil phase viscosity and density with hydration layer rupture. Additionally, an extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory was employed to investigate changes in interaction energy, further reinforcing the study's findings. This research contributes novel insights and assistance to the comprehension and application of hydration layers in other membrane studies dedicated to oil-water separation.
研究领域:
环境科学
·
材料科学
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产品关联
DOI
PubMed
高影响因子
ACS Applied Nano Materials
·
2018
·
IF 0
Jinjin Li,Zengpei Dou,Yuhong Liu,Jianbin Luo,Jinxin Xiao
Although surfactant micelles usually exhibit superlow friction at the nanoscale due to the formation of the hydration layer, the load-bearing capacity (LBC) is limited. In this study, the friction behaviors of two different surfactant micelles (fluorinated and hydrocarbon surfactants, denoted as F-surfactant and H-surfactant) were compared, with the results showing that both can achieve superlow friction (μ = 0.001–0.002) when the self-assembled micelle layers on the two surfaces were not ruptured. Although the two different surfactant micelles have the similar friction behaviors, the LBC of superlow friction for the F-surfactant is 2.5 times larger than that for the H-surfactant. The mechanisms of the superlow friction and the reasons for different LBC were investigated using an atomic force microscopy. The superlow friction can be attributed to the formation of hydration layer on the surfactant headgroups, whereas the higher LBC for F-surfactant originates from the fatness of its carbon chain, which produces the larger hydrophobic attraction and meanwhile increases the stiffness of the micelle layer.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
DESALINATION
·
2024
·
IF 8.3
Yangyang Wei,Xueli Gao,Guorong Xu,Jian Wang,Xiaojuan Wang,Xinxia Tian,Congjie Gao,Yushan Zhang
Laminated graphene oxide (GO) membrane has great potential for desalination , but achieving good stability in salt retention and water permeation is still a challenge. The “compact” sieving structure and the “loose” permeating structure of the GO membranes offer synergetic effects for high-performance desalination. Here, a composite desalination membrane involving two two-dimensional layered nanomaterials with opposite charges has been reported. The multi-layered GO (MLGO) and hydrotalcite (HT) were then alternated in a spray-coating on a PDA-modified substrate to construct multiple structures. Different assembly regions were identified by in-situ morphology monitoring, which showed that MLGO and HT were connected by electrostatic attractions . Also, the composite membrane showed high salt retention, permeability and long-term performance stability. The water flux of the composite membrane increased from 2.8 L m −2 h −1 bar −1 to 3.6–5.2 L m −2 h −1 , which was due to the increases in the interlayer spacing distances and the introduction of new permeable spaces. After a 400 h continuous filtration test, the Na 2 SO 4 retention remained stable. The water fluxes were in the range of 2.0–3.0 L m −2 h −1 bar −1 , which corresponded to an increase by 42.9 %–114.3 % in comparison with the pure MLGO membrane. As compared with the MLGO membrane, molecular dynamics (MD) simulations revealed that more water molecules passed through the MLGO-HT membrane with a shorter pathway length and higher speed than MLGO membrane. The present study demonstrated the potential of a composite with 2D materials for desalination applications .
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
PROGRESS IN ORGANIC COATINGS
·
2018
·
IF 2.955
Dan Shang,Xiaoying Sun,Xiaoyao Shen,Jianzhong Hang,Lujiang Jin,Liyi Shi
Amphiphilic xerogel films with slight swelling were prepared by the acid-catalysed sol-gel method starting from tetraethoxysilane (TEOS), triethoxyoctylsilane (C8Si), n -octadecyl trimethoxysilane (C18Si) and poly(ethylene glycol) siloxane (PEG-TMS). In these amphiphilic xerogel films, the presence of hydrophobic chains, especially C18Si facilitated the emigration of PEG chain to the coating/air interface during the film formation/curing process, and then the PEG chains enriched at the surface of coatings further slightly emigrated to form hydration layer underwater confirmed by energy dispersive X-ray spectroscopic (EDS) analysis, captive air-bubble contact angle (CA) and CA hysteresis. Furthermore, the amphiphilic xerogel films showed the optimal water absorption ratio lower than 1.0% due to the restraint of higher crosslinked density and little network aperture of the films on PEG chains. The antifouling performances of amphiphilic xerogel films included the protein resistance for FITC-BSA, antibacterial property for Escherichia coli and the resistance for diatom Navicula , were better than those of the elastic silicone-based coatings and xerogel film without hydrophilic PEG chains. In general, the amphiphilic xerogel films containing both PEG and proper levels of C8Si and C18Si possessed excellent fouling release properties and slight swelling due to the synergistic effects.
研究领域:
材料科学
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生物医学工程
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海洋生物学
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产品关联
DOI
高影响因子
LANGMUIR
·
2012
·
IF 4.186
Jiang Wu,Shengfu Chen
The strong surface hydration layer of nonfouling materials plays a key role in their resistance to nonspecific protein adsorption. Poly(ethylene glycol) (PEG) is an effective example of materials that can resist nonspecific protein adsorption and cell adhesion. Thus, the strong interaction between water molecules and PEG was investigated through each T2 component in water/PEG mixtures using multiexponential inversion of T2 relaxation time measured by the Carr–Purcell–Meiboom–Gill (CPMG) sequence of low-field nuclear magnetic resonance (LF-NMR). Results show that about one water molecule is tightly bound with one ethylene glycol (EG) unit, and additional water molecules over 1:1 ratio mainly swell the PEG matrix and are not tightly bound with PEG. This result was also supported by the endothermic behavior of water/PEG mixtures measured by differential scanning calorimetry (DSC). It is believed that the method developed could be also applied to investigate various interactions between macromolecules and other small molecules without using deuterium samples, which might open a novel route to quantitatively measure guest–host interactions in the future.
研究领域:
材料科学
·
生物化学
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产品关联
DOI
PubMed
高影响因子
ADVANCED MATERIALS
·
2024
·Vol. 36
·期 44
·2407507
·
IF 27.4
Zhen Tang,Shiquan Lin,Zhong Lin Wang
Water is crucial for various physicochemical processes at the liquid–solid interfaces. In particular, the interfacial water, mediating the electric field and solvation effect along with the solid, corporately determine the electrochemical properties. Understanding the interaction between solid properties and the interface water holds significant importance in interfacial dynamics. However, the impact of alterations in the charged state of solid surfaces induced by contact electrification on interfacial water remains unknown. Here, the evolution of atomic-level resolution maps of hydration layers are reported on charged surfaces using 3D atomic force microscopy (3D-AFM). These findings demonstrate that electrostatic interactions can reinforce, distort, or collapse the characteristic structure of hydration layers. More importantly, these interactions exhibit interlayer differences and sample specificity in hydration layer structures of different substrates. In addition, similar oscillations of the hydration layer are observed at the electrochemical interface under different voltage biases. This suggests that contact-electrification has the potential to serve as a novel method for manipulating and regulating chemical reactions at the interface.
研究领域:
表面科学
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物理化学
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电化学
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纳米材料
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界面动力学
✓ 已验证
DOI
高影响因子
DESALINATION
·
2024
·
IF 8.3
Yin-Shuang Hu,Shuo-Chun Ke,Yu-Xi Huang
Membrane fouling and scaling are two critical challenges in membrane distillation (MD). The traditional superhydrophobic anti-scaling strategy is contradictory to the hydrophilic anti-fouling coating, creating a crucial challenge to combine these two properties into one material. In this study, glutamic acid (GA) was grafted on a polyvinylidene fluoride (PVDF) membrane surface to achieve fouling and scaling resistance simultaneously. The hydrophilic GA modification endowed the membrane with a larger underwater oil contact angle without affecting the surface morphology. The direct contact MD (DCMD) tests demonstrated that the GA-modified membrane had excellent oil fouling resistance due to the formation of a hydration layer by the GA molecules. In addition, the surface carboxyl groups offered plenty of coordination sites for metal ions, such as calcium ions. The surface coordination of calcium resulted in a lower free calcium concentration on the membrane surface, thereby postponing the scale nucleation and preventing the scales from intruding into the membrane matrix. The scaling tests also showed that the gypsum scales grown on the modified membrane were smaller than those on the pristine PVDF membrane. Besides, membrane cross-section analyses revealed that no scale intrusion was observed in the GA-modified membrane. Long-term stability tests and practical application with ethylene plant spent caustic further confirmed the promising application potential of the membrane. These results demonstrated that anti-fouling and anti-scaling properties can be integrated using the GA modification. This study provides a new surface modification strategy for designing and fabricating a robust anti-fouling and anti-scaling MD membrane.
研究领域:
材料科学
·
化学工程
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
LANGMUIR
·
2019
·
IF 3.683
Sizhe Liu,Qian Zhang,Ying Han,Yulong Sun,Yifei Zhang,Hongyu Zhang
In clinics it is extremely important for implanted devices to achieve the property of enhanced lubrication and bacterial resistance; however, such a strategy has rarely been reported in previous literature. In the present study, a surface functionalization method, motivated by articular cartilage-inspired superlubrication and mussel-inspired adhesion, was proposed to modify titanium alloy (Ti6Al4V) using the copolymer (DMA–MPC) synthesized via free radical copolymerization. The copolymer-coated Ti6Al4V (Ti6Al4V@DMA–MPC) was evaluated by X-ray photoelectron spectroscopy, water contact angle, and Raman spectra to confirm that the DMA–MPC copolymer was successfully coated onto the Ti6Al4V substrate. In addition, the tribological test, with the polystyrene microsphere and Ti6Al4V or Ti6Al4V@DMA–MPC as the tribopair, indicated that the friction coefficient was greatly reduced for Ti6Al4V@DMA–MPC. Furthermore, the bacterial resistance test showed that bacterial attachment was significantly inhibited for Ti6Al4V@DMA–MPC for the three types of bacteria tested. The enhanced lubrication and bacterial resistance of Ti6Al4V@DMA–MPC was due to the tenacious hydration shell formed surrounding the zwitterionic charges in the phosphorylcholine group of the DMA–MPC copolymer. In summary, a bioinspired surface functionalization strategy is developed in this study, which can act as a universal and promising method to achieve enhanced lubrication and bacterial resistance for biomedical implants.
研究领域:
材料科学
·
生物医学工程
·
表面化学
·
摩擦学
·
生物材料
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产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Zhi Qu,Yan Sun
The enormous accumulation of poly(ethylene terephthalate) (PET) waste has posed a serious threat to the environment and human health, and biodegradation with PET hydrolase (PETase) can be a possible solution. Herein, we propose site-specifically modifying PETase with amphiphilic polymers to improve the enzyme performance at ambient temperature. For this purpose, we devise a computer-aided strategy to prioritize the conjugation site, and polyethylene glycol (PEG) preparations of 0.55 to 10 kDa are site-specifically conjugated to PETase. The most active conjugate PETase–PEG 5k (PETase-5K) shows an increase of melting temperature (3.88 °C) and significantly improves PET degradation performance (3.5- and 3.1-fold increases at 30 and 40 °C, respectively). Experimental investigation and molecular dynamics simulations reveal that the site-specific PEGylation increases the hydrophobic solvent-accessible surface area and the binding capability to the PET surface, thickens the hydration layer, increases the intramolecular hydrogen bonding, reduces the interactions between water and the conjugated enzyme surface, and rigidifies the enzyme structure via hydrogen bonding and hydrophobic interactions between the polymer and the enzyme, thus leading to improved enzymatic performance of PETase-5K. We further validate the versatility of the site-specific PEGylation in one of the most evolved variants of PETase, FAST-PETase, by 1.8-fold improvement in PET degradation at 30 °C. The presented computer-aided site-specific conjugation strategy has opened a new avenue to enhancing PETase performance at ambient temperature, and the contribution of PEGylation to PETase unraveled in this work laid a foundation for the rational engineering of PET hydrolases.
研究领域:
环境科学
·
生物化学
·
生物技术
·
分子生物学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2024
·
IF 8.4
Gansheng Liu,Christine N. Matindi,Zhiyou Pu,Sania Kadanyo,Zhenyu Cui,Jianhua Yang,Jianxin Li
Zwitterionic polysulfone (PSf) ultrafiltration membranes were fabricated by non-solvent phase separation (NIPS) method. Herein, a casting solution at 45 °C was developed by using chloromethylated polysulfone (CMPSf), N, N-dimethylacetamide (DMAc) as a solvent, 4-amino-benzenesulfonic acid monosodium salt (ABS) as a cross-linking agent, and Na 2 CO 3 as an acid binder. Simultaneously, the occurrence of the electrophilic substitution reaction between ABS and CMPSf caused the formation of ABS grafting CMPSf (CMPSf-g-ABS). After a specific reaction time, the casting solution was applied to cast membranes, which were subsequently submerged in coagulation bath. A zwitterionic ultrafiltration (ZUF) membrane was obtained using NIPS following the treatment of hydrochloric acid (HCl) solution (1 M mol). Because of the formation of cross-linked CMPSf-g-ABS, the results revealed that the casting solution's viscosity increased sharply from 425.4 mPa s at the initial stage (0 h) to 4810.8 mPa s (22 h). Interestingly, the morphology of the membranes with an asymmetric finger-like structure at 0 h gradually transformed to a gradient sponge-like structure after 22 h. Specifically, the ZUF membrane (M22-H) with the gel fraction of 72.1% procured after the reaction of 22 h demonstrated a low water contact angle (40.17°) and a high pure water permeance (420.4 L m −2 h −1 bar −1 ). The M22-H also exhibited a high flux recovery rate (FRR) (90.2%), bovine serum albumin (BSA) rejection (>95%), and Escherichia coli ( E. coli ) antibacterial rate (96.2%). The surface of the ZUF membrane with numerous zwitterionic groups enhances the hydration layer's energy (i region <16 nm) and creates a thick hydration layer (ii region >16 nm), causing a significant improvement in the antifouling performance. This research opens new avenues for preparing zwitterionic functional membranes.
研究领域:
材料科学
·
膜技术
·
环境工程
·
化学工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）