JOURNAL OF MEMBRANE SCIENCE
·
2021
·
IF 8.742
Longzhu Zheng,Hongqiang Li,Xuejun Lai,Wei Huang,Zengyue Lin,Xingrong Zeng
With the increasing environmental pollution caused by oily wastewater and oil spill accidents, many superwettable materials have been prepared and applied for the separation of oil-water mixtures. However, the fabrication of superwettable materials for multifunctional water purification including oil-in-water and water-in-oil emulsion separation, dyes degradation and heavy metal ions removal still remains challenging. Herein, we propose a facile method to fabricate a superwettable Janus nylon membrane through in situ generation of silver (Ag) particles immobilized by polydopamine and asymmetric chemical modification with dodecanethiol (NDM) and l -cysteine (L-cys) on the positive and negative surfaces, respectively. The positive surface modified by NDM exhibited superhydrophobicity and superoleophilicity, and the negative surface chemically bonded with L-cys possessed opposite wettability with superhydrophilicity and underwater superoleophobicity. The positive and negative surfaces of the Janus membrane were respectively applied for the separations of water-in-oil emulsions and oil-in-water emulsions, and the separation efficiencies all reached above 99%, also demonstrating great reusability and wide adaptability. In addition, the Janus membrane presented not only outstanding performance of degrading methylene blue (MB) with high efficiency above 97.3%, but also excellent capability of absorbing heavy metal ions in the process of emulsion separation. The fabrication processes are facile, mild, and no special equipment is involved, and our findings conceivably provided a new strategy to fabricate superwettable Janus membrane for multifunctional emulsion separation and wastewater purification.
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Xiaoyan Yu,Sibo Kang,Xiaoyu Jiao,Hua Lai,Ruijie Wang,Zhongjun Cheng
Recently, Janus membranes with particular ability in unidirectional water permeation, known as “water diode”, have attracted increased attention. However, almost all existing Janus membranes are focused on controlling water permeation in air, similar membranes can work in complicated environments, such as oil, are still quite unusual, let alone with smart controllability. Herein, we report a TiO 2 nanostructures coated mesh membrane. The membrane’s surface wettability can be reversibly switched between uniformly underoil superhydrophobicity and Janus underoil hydrophobicity/hydrophilicity as unilateral UV irradiation and heating are alternately carried out, consequently, on/off control of water permeation between blocking state and unidirectional penetrating state can be realized. Moreover, by controlling the size of the region irradiated by UV light for 50 min, penetrating channels with controlled size can be designed. Based on this advantage, different independent penetrating channels with diameter from 2 mm to 10 mm can be obtained, and precise control of water permeation flux from 48,432 Lm −2 h −1 to 70,553 Lm −2 h −1 can be achieved. Finally, based on the excellent controllability, some significant applications such as the removal of water from oil, underoil multichannel chemical reaction, and droplet pumping were also demonstrated. This work reports a new membrane with smart underoil water permeation controllability, given its controllability and particular wetting performance, it is potentially used in many fields, for example, oil purification, droplet manipulation, and microfluidic devices .
研究领域:
材料科学
·
界面化学
·
微流控技术
✓ 已验证
产品关联
DOI
高影响因子
WATER RESEARCH
·
2023
·
IF 12.8
Danting Shi,Tengjing Gong,Rui Wang,Weihua Qing,Senlin Shao
Janus membranes with asymmetric wettability have attracted wide attentions for their robust anti-oil-wetting/fouling abilities in membrane distillation (MD). Compared to traditional surface modification approaches, in this study, we provided a new approach which manipulated surfactant-induced wetting to fabricate Janus membrane with a controllable thickness of the hydrophilic layer. The membranes with 10, 20, and 40 μm of wetted layers were obtained by stopping the wetting induced by 40 mg L −1 Triton X-100 ( J = 25 L m −2 h −1 ) at about 15, 40, and 120 s, respectively. Then, the wetted layers were coated using polydopamine (PDA) to fabricate the Janus membranes. The resulting Janus membranes showed no significant change in porosities or pore size distributions compared with the virgin PVDF membrane. These Janus membranes exhibited low in-air water contact angles (< 50°), high underwater oil contact angles (> 145°), and low adhesion with oil droplets. Therefore, they all showed excellent oil-water separation performance with ∼100% rejection and stable flux. The Janus membranes showed no significant decline in flux, but a trade-off existed between the hydrophilic layer thicknesses and the vapor flux. Utilizing membranes with tunable hydrophilic layer thickness, we elucidated the underlying mechanism of such trade-off in mass transfer. Furthermore, the successful modification of membranes with different coatings and in-situ immobilization of silver nanoparticles indicated that this facile modification method is universal and can be further expanded for multifunctional membrane fabrication.
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
DESALINATION
·
2025
·
IF 9.8
Rui Zhang,Yunhuan Chen,Hailong Wang,Xugang Song,Qiang Ma,Xiaoxiao Duan,Yongsheng Ren
Membrane distillation (MD) technology encounters problems such as membrane scaling, membrane wetting, and fouling during the reprocessing of diverse wastewater types. Janus membranes are anticipated to hold significant potential in addressing these issues. The metal-polyphenol network (MPN) was employed to mediate the catalytic self-cleaning ability of the intermediate mineralization layer as well as the PA-layered Janus membranes generated on the surface through the interfacial polymerization (IP) reaction. It was revealed that the pure water flux of the pristine PVDF membrane was 44.9 LMH, while that of the Janus membrane was 41.8 LMH. The PA layer of the Janus membrane is conducive to the increase of flux because of its hydrophilicity. However, excessive nanoparticles can block the membrane pores, and thus it compensates for part of the decreased flux to a certain extent. During the direct contact membrane distillation (DCMD) experiment, Janus membrane demonstrated superior performance in comparison to the PVDF membrane in the treatment of oily wastewater, saline solutions of sodium dodecyl sulphate (SDS), and gypsum-induced fouling. The mineralization layer based on manganese oxide can ensures higher stability of Janus membranes during cycling through in situ catalytic self-cleaning when dealing with the organic pollutant humic acid (HA). Overall, this study offers a novel and potential MD membrane.
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
Materials Today Sustainability
·
2024
·
IF 7.1
Yuyan Guo,Zhiguang Guo,Weimin Liu
Inspired by the capillary effect in nature (such as water transport in soils) and droplet-drive performance of Nepenthes, a new driving strategy for emulsion separation membrane based on the synergistic effect of capillary force and progressive wettability-induction force was proposed. It is prepared by a one-step, simple continuous, electrospinning process. By adjusting solutions and spinning parameters, the membrane obtains its capillary structure and progressive oleophilicity in one-step preparation. Attractively, the membrane shows separation efficiency and excellent permeability, with a flux of 384801 L m −2 h −1 bar −1 for the oil-water mixture, and the little water content of less than 18 ppm. And for emulsions, the flux even reaches 50000 L m −2 h −1 bar −1 and the separation efficiency reaches 99.95%. Furthermore, the membrane has excellent mechanical-stability: at 80 kPa transmembrane pressure, it can still effectively prevent water's penetration. Drawing inspiration from nature, the incorporation of capillary force and progressive wettability-induction force into the separation membrane as an additional dual emulsion separation driving force proves to be a highly effective and versatile approach. This method provides a way to solve the general flux-efficiency balance problem of oil-water separation and also provides a new strategy for the preparation of separation membranes for various purposes.
研究领域:
材料科学
·
环境工程
·
仿生学
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2025
·
IF 19
Yinan Li,Liulian Huang,Zhibin He,Jianguo Li,Chenglong Fu,Qinghong Zheng,Lihui Chen,Yonghao Ni
Solar-driven evaporators have emerged as a sustainable strategy for water purification and energy harvesting. Designing advanced systems that achieve high evaporation performance, long-term operational stability, and resistance to salt crystallization remains a significant challenge. In this study, an innovative Janus membrane is proposed that addresses these challenges, featuring a super hydrophilic cellulose nanofiber (CNF)@Hexadecyl Trimethyl Ammonium Bromide (CTAB)-MXene layer and a superhydrophobic polytetrafluoroethylene (PTFE) layer. CTAB modification of MXene enhances its interlayer spacing and specific surface area, enabling rapid water transport and efficient solar energy absorption of the CNF@CTAB-MXene layer. A PTFE layer is sputter-deposited onto CNF@CTAB-MXene layer, effectively preventing salt accumulation and membrane fouling, with plasma pre-treatment ensuring excellent interfacial bonding between these two layers. Under 1 sun illumination, the CNF@CTAB-MXene/PTFE Janus evaporator achieves a remarkable evaporation rate of 1.51 kg m −2 h −1 with outstanding salt resistance. The synergy between superhydrophilic and superhydrophobic layers facilitates efficient water transport while maintaining long-term stability without performance degradation. Additionally, the evaporator generates a voltage of 343.8 mV during thermoelectric power generation, and its unique design allows electricity generation from wind energy at night. This integrated system provides an advanced and durable solution for water-power co-generation, offering practical benefits for off-grid or remote regions.
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
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Liyong Wang,Mingming Liu,Yongling Wu,Hongyu Zheng
Superwetting functional surfaces based on laser-induced graphene (LIG) have a wide range of applications in many fields. However, single wettability LIG films are difficult to respond to complex and changing environmental conditions. Despite the large number of experiments were carried out to demonstrate the formation of LIG, there is a lack of studies on the process and formation mechanisms of LIG. In this study, the conversion of PEI to graphene was systematically investigated by both experimental and molecular dynamics simulations. A new method for obtaining Janus membranes with both superhydrophobicity and superhydrophilicity by ethanol and plasma treatment of LIG is proposed. The asymmetrically superwetting Janus membrane are shown to realize the on-demand controllable separation of light oil–water and heavy oil–water. In addition, the superhydrophobic LIG is used as a coating material with excellent electrothermal properties, which provide the performance of anti-icing and electrothermal de-icing. The asymmetrically superwetting Janus membranes prepared by the proposed simple and environmentally friendly method are shown to have a variety of prospective applications.
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
ADVANCED MATERIALS
·
2024
·
IF 27.4
Yongxiang Han,Yanlei Wang,Mi Wang,Hao Dong,Yi Nie,Suojiang Zhang,Hongyan He
Harvesting electricity from widespread water evaporation provides an alternative route to cleaner power generation technology. However, current evaporation power generation (EPG) mainly depends on the dissociation process of certain functional groups (e.g., SO 3 H) in water, which suffers from low power density and short-term output. Herein, the Janus membrane is prepared by combining nanofluid and water-grabbing material for EPG, where the nanoconfined ionic liquids (NCILs) serve as ion sources instead of the functional groups. Benefiting from the selective and fast transport of anions in NCILs, such EPG demonstrates excellent power performance with a voltage of 0.63 V, a short-circuit current of 140 µA, and a maximum power density of 16.55 µW cm −2 while operating for at least 180 h consistently. Molecular dynamics (MD) simulation and surface potential analysis reveal the molecular mechanism, that is, the diffusion of Cl − anions during evaporation is much faster than that of cations, generating the voltage and current across the membrane. Furthermore, the device performs well in varying environmental conditions, including different water temperatures and sources of evaporating water, showcasing its adaptability and integrability. Overall, the nanofluid-guided Janus membrane can efficiently transform low-grade thermal energy in evaporation into electricity, showing a competitive advantage over other sustainable applied approaches.
研究领域:
材料科学
·
能源技术
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2018
·
IF 6.578
Hai-Ming Song,Cheng Chen,Xiao-Xue Shui,Hao Yang,Li-Jing Zhu,Zhi-Xiang Zeng,Qun-Ji Xue
Although Janus membranes have been fabricated for the separation of oil/water mixtures, simplifying the construction processes is still a thorny challenge. In this work, a facile and easily scale-up approach based on in situ mussel-inspired chemistry is reported for the first time to prepare the Janus membrane with unidirectional oil/water separation. Here, the poly (vinylidene fluoride)/polydopamine/polyethylenimine (PVDF/PDA/PEI) membranes on the polyester non-woven fabric were fabricated via non-solvent induced phase separation (NIPS) technique. In the coagulation bath, the reactive oxygen species (ROS) produced by CuSO 4 /H 2 O 2 improved the formation of the hydrophilic PDA/PEI on the top surface of the membrane. The hydrophobic bottom surface was received after the membrane was stripped from the supporting fabric. Scanning electronic microscopy (SEM), confocal laser scanning microscopy (CLSM), attenuated total reflectance Fourier transform infrared spectrometer (ATR-FTIR), X-ray photoelectron spectroscopy (XPS) and energy dispersive spectrometer (EDS) were used to characterize the membrane. The Janus membrane showed asymmetric wettability with 152.2° underwater oil contact angle of F-T5 and 153.3° underoil water contact angle of B-T5. Furthermore, by this in situ mussel-inspired chemistry, the Janus membrane showed excellent water and oil separation, antifouling performance and stability, which can potentially be used for unidirectional oil/water separation.
研究领域:
材料科学
·
环境科学
·
界面化学
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2018
·Vol. 53
·期 20
·14398-14411
·
IF 2.993
Zhang Cheng,He Shuai,Wang Dingfei,Xu Fang,Zhang Fengxiu,Zhang Guangxian
A novel smart Janus membrane for unidirectional water transfer and oil–water separation is facilely fabricated by coating graphene nanoplatelets (GNs) onto one side of polyethylene terephthalate (PET) fabric through high-temperature and high-pressure method and subsequently grafting phosphoric acid (HP) into the other side of PET fabric. Results suggest that the prepared HP–PET–GNs Janus membrane with heterogeneous surface wettability attributed to the hierarchical structure of membrane shows special unidirectional water transfer property. The water droplet can penetrate across the membrane from the GNs-coated (hydrophobic) side to the HP-grafted (hydrophilic) side, and be blocked to pass through the membrane from hydrophilic side to hydrophobic side. Moreover, the HP–PET–GNs Janus membrane is found to have the maximum water flux and separation efficiency of 2073 ± 207 Lm −2 h −1 and 99.5 ± 0.2% for methylbenzene–water mixture, and the maximum oil flux and separation efficiency of 3113 ± 52 Lm −2 h −1 and 99.6 ± 0.1% for carbon tetrachloride–water mixture, respectively. The water separation efficiency and oil separation efficiency could arrive at 99.0 ± 0.1 and 99.3 ± 0.2% even after 10 separation cycles, respectively. It is revealed that the obtained Janus membrane has excellent separation capability for separating the layered oil–water mixtures and possesses wonderful recyclability.
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
DESALINATION
·
2022
·
IF 11.211
Simin Li,Liangzhong Li,Jiahao Zhong,Ruixue Ma,Xiaohang Xu,Huiguang Wu,Yang Yu
A novel Janus membrane was fabricated by constructing a thin hydrophobic layer with beads-on-string structure on the surface of superhydrophilic polyacrylonitrile (PAN) electrospun nanofiber (ENs) substrate through hybrid electrospinning and electrospraying techniques. The electrosprayed polystyrene/poly(dimethylsiloxane) (PS/PDMS) beads were interlinked by nanofibers and further anchored by 3-D network formed by electrospinning polyvinylidene fluoride-co-hexafluoropropylene (PH). Surface roughness and morphology of formed beads and relevant hydrophobic layers could be highly affected by weight ratios and concentrations of PS and PDMS. The hydrophobic layer (PH-7PS/7PDMS) prepared by electrospraying PS/PDMS (7 wt%/7 wt%) mixed solution showed the highest water contact angle (WCA) value of 148.5 o and the largest surface roughness of 812 nm. The optimized Janus membrane could exhibit a water flux of 27.7 L/m 2 h and a salt rejection efficiency close to 100 % at the temperature difference of 40 °C when 3.5 wt% sodium chloride (NaCl) was used as the feed solution. The addition of PDMS could endow the Janus membrane with better performance stability and anti-fouling ability due to the enhanced surface hydrophobicity and formation of unique multi-level roughness on the hydrophobic layer. The prepared Janus membrane could be used as a promising candidate for the direct contact membrane distillation (DCMD) process.
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
CHEMOSPHERE
·
2022
·
IF 8.943
Zhongbao Ma,Long-Fei Ren,Diwen Ying,Jinping Jia,Jiahui Shao
The separation of hardness ions such as calcium and magnesium from hard water can improve water quality, which is important but technically challenging. Nanofiltration (NF) has attracted much attention because of its efficiency, environmental friendliness and low cost. However, common NF membranes with a singly (either positively or negatively) charged layer have insufficient water softening capacity. In this work, two types of dual-layer Janus charged polyamide NF membranes composed of oppositely charged inner and outer layers were developed for the first time by sequential electrospray polymerization strategy for efficient water softening. The effect of the microstructure of the dually charged barrier layer on the separation performance of divalent salt ions was explored. Detailed mechanistic studies revealed that the microstructure of the outer layer of the barrier layer played a crucial role in the ion separation of the Janus membrane due to its control of the reverse transport of ions. Janus charged polyamide NF membrane with a loose outer layer exhibited better water softening performance (93.6% of hardness removed) compared to the singly charged NF membranes due to the simultaneous dual electrostatic effect and no ion reverse transport confinement. This Janus charged NF membrane also possessed good antifouling performance, mainly due to its negatively charged outer layers. The mechanistic insights gained in this study reveal the huge potential of microstructural design toward high-performance Janus charged NF membranes, and provide important guidance on the future development of high-efficiency water softening NF membranes.
研究领域:
材料科学
·
环境工程
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）