AIP Advances
·
2019
·Vol. 9
·期 11
·
IF 1.579
Zhang Jianwen,Cao Peng,Cui Zhaoliang,Wang Qian,Fan Fan,Qiu Minghui,Wang Xiaozu,Wang Zhaohui,Wang Yong
Membrane fouling can be efficiently mitigated by the vibration of the piezoelectric membrane stimulated by AC signals, but it is still a challenge to fabricate piezoelectric membranes with great efficiency, low energy-consumption, and no harm to the environment during its preparation. The present work provides a new approach to poly(vinylidene fluoride) (PVDF) membranes with piezoelectric properties by directly poling β-phase PVDF membranes using green diluents, which revealed better piezoelectric properties than poling α-phase PVDF membranes. Basically, absolute β-phase crystals of PVDF membranes were induced over thermally induced phase separation with the addition of Acetyl tributyl citrate (ATBC)/ionic liquid ([BMIM]PF 6 ), which are regarded as green and environment-friendly diluents. To endow the piezoelectric property to the β-phase PVDF membrane, a poling process was necessarily conducted. The effect of the poling process on the membrane structure, morphologies, properties, and performances was investigated. Meanwhile, a vibration test for both of the poled and unpoled membranes was performed in an excitation of the alternating signal. The results demonstrated that the poling process positively endowed the piezoelectric property to the PVDF membranes. The membrane structure, morphologies, and performances of the membranes were also changed to some extent by the poling process. Additionally, filtrations of the poled membrane both with and without electrical signals were carried out to test their antifouling performance on the CaCO 3 suspension system and BSA solution, respectively. It was observed that the stable flux of the membranes notably improved when subjected to an electrical AC signal. Thus, it depicted that the piezoelectric PVDF membrane directly poled from the β-phase possesses a promising antifouling performance due to its high piezoelectric vibration.
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
Membranes
·
2023
·Vol. 13
·期 10
·807
·
IF 4.2
Yixia Zhao,Zehao Zhang,Yan Zhang,Yuting Huang,Yanfei Chen,Bofei Chen,Weimin Kang,Jingge Ju
Recently, the multi-level interwoven structured micro/nano fiber membranes with coarse and fine overlaps have attracted lots of attention due to their advantages of high surface roughness, high porosity, good mechanical strength, etc., but their simple and direct preparation methods still need to be developed. Herein, the multi-level structured micro/nano fiber membranes were prepared novelly and directly by a one-step electrospinning technique based on the principle of micro-phase separation caused by polymer incompatibility using polystyrene (PS) and polyvinylidene fluoride-hexafluoropropylene copolymer (PVDF-HFP) as raw materials. It was found that different spinning fluid parameters and various spinning process parameters will have a significant impact on its morphology and structures. Under certain conditions (the concentration of spinning solution is 18 wt%, the mass ratio of PS to PVDF-HFP is 1:7, the spinning voltage is 30 kV, and the spinning receiving distance is 18 cm), the PS/PVDF-HFP membrane with optimal multi-level structured micro/nano fiber membranes could be obtained, which present an average pore size of 4.38 ± 0.10 μm, a porosity of 78.9 ± 3.5%, and a water contact angle of 145.84 ± 1.70°. The formation mechanism of micro/nano fiber interwoven structures was proposed through conductivity and viscosity tests. In addition, it was initially used as a separation membrane material in membrane distillation, and its performance was preliminarily explored. This paper provides a theoretical and experimental basis for the research and development of an efficient and feasible method for the preparation of multi-level micro/nano fiber membranes.
研究领域:
材料科学
·
化学工程
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
POLYMER
·
2024
·
IF 4.1
Yongjing Fu,Huijia Wang,Chuan Zhou,Yiming Wang,Ni Li
Heat insulation and solar energy use are attractive strategies to cope with the serious and external cold environment. Here, silver nanowires (AgNWs) with high purity and aspect ratio were synthesized by polyol method and PVDF/AgNWs nanofiber membranes were prepared by electrostatic spinning. We investigated the warmth retention properties of nanofiber membranes using a heating table and simulated sunlight as the heat source, respectively. The results showed that the nanofiber membrane doped with 2 wt % AgNWs had a high porosity of 84% and thus a low thermal conductivity of 18 mW m −1 K −1 . Meanwhile the nanofiber membrane exhibited stable and long-lasting heat insulation behaviors and the surface temperature of the fiber membrane could reach nearly 43 °C after 5 min of irradiation with a 100 mW cm −2 light intensity and about 70 °C after 2 min of irradiation with a 300 mW cm −2 light intensity. In addition, the nanofiber membrane showed hydrophobicity with a water contact angle of 138° and breathability with air permeability of 75 mm s −1 . The stress and strain of the nanofiber membrane was 3.6 Mpa and 211.3% respectively.
研究领域:
材料科学
·
能源科学
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2019
·
IF 5.107
Xiaodi Liu,Haikuan Yuan,Chengcong Wang,Shuai Zhang,Lijuan Zhang,Xijian Liu,Fengjiao Liu,Xueyan Zhu,Sohrab Rohani,Chibun Ching,Jie Lu
In this work, PFSA-g-GO nanocomposites were firstly prepared by perfluorosulfonic acid (PFSA) grafted on graphene oxide (GO) in various mass ratios through an esterification reaction. Then a series of PVDF/PFSA-g-GO ultrafiltration (UF) membranes were constructed by a non-solvent induced phase separation (NIPS) method using the obtained diverse PFSA-g-GO nanocomposites as additives in different dosages. PFSA-g-GO nanocomposites and PVDF/PFSA-g-GO membranes were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscope (SEM), atomic force microscope (AFM), water contact angle, etc. The UF performance was examined using the separation of bovine serum albumin (BSA) and humic acid (HA) as a model system. The results showed that, compared with those of PVDF membrane, the permeability and the antifouling capacity of proposed PVDF/PFSA-g-GO membranes were enhanced. For example, the pure water flux of membrane M4 (PFSA:GO mass ratio of 2.5:1, fraction of PFSA-g-GO in dope solution of 0.5 wt%) was 1.5 times higher than that of PVDF membrane, but in the meantime, the rejection of BSA and HA was up to 93.9% and 79.6%, respectively. In general, the presence of PFSA-g-GO nanocomposites in dope solutions increased the hydrophilicity and decreased the roughness of membrane surfaces, and meanwhile increased the porosity and the pore size of membranes, which was dependent upon the content and the PFSA to GO mass ratio of nanocomposites in membranes.
研究领域:
材料科学
·
环境工程
·
生物技术
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS & DESIGN
·
2020
·
IF 6.289
Yanan Hao,Zunpeng Feng,Zhengda He,Jiameng Zhang,Xiaoming Liu,Jing Qin,Limin Guo,Ke Bi
Dielectric capacitors are key devices in pulsed power systems for their high power density. To improve the energy density, compact nanocomposite films comprising PVDF polymer and core-shell BaTiO 3 @TiO 2 nanoparticles are prepared, in which the BaTiO 3 ( d ~ 8 nm) nanoparticles are encapsulated by the amorphous TiO 2 shell layer. Compared to the conventional BaTiO 3 /PVDF nanocomposite, the BaTiO 3 @TiO 2 /PVDF nanocomposite in this report takes advantage of the small particle size and the gradient dielectric design of the interface, which enhances the electric displacement as high as 65% and the breakdown strength of 20% simultaneously. A maximal discharged energy density of 11.34 J·cm −3 is achieved under an electric field of 420 kV·mm −1 in the nanocomposite film containing 5 vol% BaTiO 3 @10 wt%TiO 2 . Therefore, the gradient design of ultrasmall dielectric nanofillers shows high potential in fabrication of high energy-density nanocomposite.
研究领域:
材料科学
·
电气工程
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Hongai Zheng,Meilin Zhu,Derui Wang,Yao Zhou,Xin Sun,Shuangyan Jiang,Mengyao Li,Cunzheng Xiao,Daquan Zhang,Lizhi Zhang
Membrane fouling is one of the main impediments that limit the wide application of Polyvinylidene fluoride (PVDF) membrane. In this study, for the first time, we incorporated the cellulose nanocrystal (CNCs) onto Cu-MOF-74 by physical stirring and then coated the composites on the PVDF membrane to ameliorate the antifouling performance. The PVDF membrane with the addition of CNC/Cu-MOF-74 composite showed enhanced hydrophilicity compared with the pristine membrane, which significantly promoted the permeability and antifouling performance. The Bovine serum albumin (BSA) multiple-cycle antifouling results revealed that the flux recovery ratio (FRR) value (76.9 %) was much higher than that of the pristine membrane (60.8 %). The enhancement of recovery flux was correlated with the increased electrostatic repulsion and hydrophilicity of the modified membrane according to the contact angle test and Zeta-potential measurement. Meanwhile, the CNC/Cu-MOF-74 modified membrane showed improved antibacterial efficiency (96.3 % at 4 h) due to the predominant antibacterial efficacy of Cu-MOF-74. The efficiently antibacterial achievement of modified membrane was attributed to the release of Cu 2+ and the generation of •OH. This study proposed a novel modified membrane with excellent antifouling properties and provided new insights into the fabrication of antifouling membranes with outstanding performance.
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
Journal of Inorganic and Organometallic Polymers and Materials
·
2024
·
IF 3.9
Li Chaoqun,Zhao Xiaojia,Wang Qi,Chen Shunzhong,Yin Fangqian,Lan Jianru,Qi Ruiyue,Peng Guirong
Polymer-based composites with excellent dielectric properties are vital component in the electronics and power systems. In order to improve dielectric constant and reduce loss of polymer, a series of flexible PVDF-based composite films containing functionalized graphene were prepared in this work. The results of TEM, FTIR, TG, and XPS showed that Methyltetrahydrophthalic Anhydride (MeTHPA) was successfully grafted onto the surface of graphene nanosheets. SEM indicated that grafted graphene nanosheets are uniformly dispersed in PVDF. Brunauer Emmett Teller (BET) analysis suggested that MGNP-PVDF composite film with a dense structure was fabricated. Compared with the PVDF-based composite film with un-grafted GNP, the introduction of MeTHPA-GNP remarkably enhanced the dielectric properties and restricted the dielectric loss and conductivity of the MGNP-PVDF composite films. When content of MeTHPA-GNP filler was 3.5%, the dielectric constant of the composite film reached 62 under 1 kHz at room temperature, and the dielectric loss maintained a low value of 0.425. The above-mentioned outstanding properties are owing to the compatibility of the ester groups in the grafted graphene nanosheets and the ester groups in the epoxy resin. This is caused by the effective encapsulation of MeTHPA molecules grafted on the surface of graphene nanosheets.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2019
·Vol. 137
·期 24
·48804
·
IF 2.188
Yan Feng,Runjun Sun,Chengkun Liu,Meiyu Chen,Qiushi Wang
The electrospun polyamide 6 (PA6) membranes are treated with different methods. The rough surfaces with different protuberances size and the fiber diameter are prepared by wet, dry heat, wet heat, and ethanol treatments under relaxation, and the formation mechanisms are analyzed. A relative stable structure of PA6 membrane is also prepared by ethanol treatment under tension, and its structure is as same as the untreated membrane. The dynamic water contact angles (WCAs) of the treated membranes are measured. The starting WCA of the membrane with wet heat treatment under relaxation is 90.95°, which is larger than those of wet, dry heat, and ethanol treatments under relaxation. The effects of surface morphologies with different treatments on wettability are analyzed. For obtaining hydrophobicity, the membrane with wet heat treatment under relaxation was coated by polyvinylidene fluoride (PVDF). The WCA of the membrane increases to 127.1° after coating. From another point of view, the WCA of the PVDF/treated PA6 membrane is much larger than that of the pure casting PVDF membrane, which means the rough surface of the treated PA6 membrane can improve the hydrophobicity of the PVDF membrane. Furthermore, the membrane is endowed with superhydrophobicity (WCA of 153.5°) after being coated by SiO 2 /PVDF due to the multilevel structured surface roughness. It is a relative low cost and convenient operation method to prepare the superhydrophobic material. The results provide a novel preparation method of the superhydrophobic material and a treatment method of the electrospun PA6 membrane to obtain a stable structure. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137 , 48804.
研究领域:
材料科学
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
LANGMUIR
·
2023
·
IF 3.9
Yujia Tong,Changing Miao,Wenlong Ding,Fiona Hammond Quarcoo,Xiao Xiao,Hongjun Ji,Weixing Li,Xiaohui Ju
The current methods of constructing modification strategies for hydrophilic membranes are time-consuming, complex in operation, and poor in universality, which limit their application on membranes. In this work, inspired by the adhesion properties and versatility of caffeic acid (CA) and p-phenylenediamine (PPDA), a simple, rapid, and universal method was designed for the separation of oil-in-water emulsion by preparing a stable hydrophilic coating separation membrane. The preparation time of the membrane was shortened to 40 min. The developed PVDF–PCA/PPDA membrane showed superhydrophilic and underwater superoleophobic properties. When applied to petroleum ether-in-water emulsion, isooctane-in-water emulsion, and dodecane-in-water emulsion separation, the oil rejection was more than 99.0%. In the circulating separation of 10 g/L soybean oil-in-water emulsion, the oil rejection was more than 99.3%, and the highest flux was 1036 L·m–2·h–1. The prepared PVDF–PCA/PPDA membrane performed well in the separation test of oily wastewater. The proposed strategy is simple and rapid; it may become a universal method for preparing membranes with super strong antifouling properties against viscous oil and accelerate the research progress of membrane separation of oil-in-water emulsions.
研究领域:
材料科学
·
环境工程
·
界面化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2023
·
IF 5.2
Jie Hu,Shenglin Yuan,Wensha Zhao,Caiwang Li,Peng Liu,Xiang Shen
The direct discharge of oily wastewater into the environment is considered one of the greatest threats to the ecological environment. Membrane technology is considered as an efficient strategy to treat oily wastewater. However, the membrane fouling caused by oil adsorption has intensively impeded its practical utilization in oil/water separation. This work aims to fabricate an anti-oil-fouling membrane for the effective separation of oil/water emulsions. The PEGylated poly(vinylidene fluoride) (PVDF) membrane was synthesized via thiol–ene photochemistry with poly(ethylene glycol) diacrylate (PEGDA) and 3,6-dioxa-1,8-octanedithiol (DOT) as the modifiers. The results of scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) mapping analysis revealed that the PEGylated layers show uniform distribution on the membrane surface by regulating the feed PEGDA concentration. The superhydrophilic and underwater superoleophobic characteristics of the PEGylated membrane provided oil-adhesion resistance to the membranes. The membrane grafted with a high amount of PEGylated layers shows a low pure water flux, due to the pore blockage. The PEGylated membrane possesses the stable surface wettability and permeation performance of emulsion. The separation efficiency of PEGylated membranes for multiple emulsions is greater than 99%, and the highest rejection value is as high as 99.9%. After the three-cycle filtration of emulsified pump oil solution, the flux recovery ratio of membranes still reaches 90%, indicating an outstanding fouling resistance to emulsified oily matters. This work provides a feasible strategy to prepare the antifouling PVDF membrane used for the oil/water separation.
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
·
2023
·
IF 8.8
Jun Young Kim,Kang Hoon Lee,Jae Won Lee,Imtiaz Afzal Khan,Jong-Oh Kim
In this study, the removal efficiency of chemicals of emerging concerns (CECs) was evaluated under exposure to various doses of UV/H 2 O 2 -based oxidation processes in combination with membrane filtration for three cleaning cycles. Polyethersulphone (PES) and polyvinylidene fluoride (PVDF) materials based membranes were used for this study. The chemical cleaning of the membranes was performed by immersion of the membranes into 1 N HCl followed by adding 3000 mg.L −1 NaOCl for 1hr. Degradation and filtration performance was evaluated using Liquid Chromatography with tandem mass spectrometry (LC-MS/MS) and total organic carbon (TOC) analysis. Membrane fouling analysis for assessing the comparative performance of PES and PVDF membranes was determined by specific fouling and fouling indices evaluation. Membrane characterization results show that the alkynes and carbonyl group formation are due to dehydrofluorination and oxidation of PVDF and PES membranes under the attack of foulants and cleaning chemicals, which resulted in a reduction of fluoride percentage and an increase in sulfur percentage in the PVDF and PES membranes. A decrease in the hydrophilicity of the membranes in underexposed conditions was observed and is consistent with an increase in dose. Degradation results of CECs follow with the highest removal efficiency of chlortetracycline (CTC) followed by atenolol (ATL), acetaminophen (ACT), and caffeine (CAF) degradation due to attack on the aromatic ring and the carbonyl group of CECs by OH exposure. Membrane exposed at 3 mg.L-1 dose of UV/H 2 O 2 -based CECs shows minimum alteration with higher filtration efficiency and lower fouling, particularly in PES membranes.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Central South University
·
2025
·Vol. 32
·期 1
·71-81
·
IF 4.4
Zhou Run-kai,Yang Hong,Peng Chao-qun,Wang Ri-chu,Zhang Dou,Fang Guang-qiang,Wang Xiao-feng
Polyvinylidene fluoride/lead zirconate titanate (PVDF/PZT) composite films have been prepared by direct ink writing and the effect of PZT content on crystallization behavior and electrical properties of film were systematically investigated. The composite films were characterized by scanning electron microscope (SEM), X-ray diffractometer (XRD), Flourier transform infrared spectroscope (FTIR) and differential scanning calorimeter (DSC). The results show that, surface modified PZT powder (PZT@PDA) is successfully coated by polydopamine (PDA), resulting in a large number of polar groups that interact with the —CF 2 — groups in PVDF, inducing the generation of polar β phase due to hydrogen bonding formed in the interaction. The β phase content in composite film increases with increasing PZT@PDA content, up to 28.09% as with 5 wt.% PZT@PDA. PZT@PDA plays a role of nucleating agent to promote the generation of polar phases in the film and also acts as an impurity hindering the growth of nuclei to reduce crystallinity. Moreover, the presence of PZT@PDA in interfaces provides more sites for the occurrence of interfacial polarization and thus improving the electrical properties of films. The composite film with 5 wt.% PZT@PDA possesses the highest dielectric constant (8.61) and residual polarization value (0.6803 µC/cm 2 ).
研究领域:
材料科学
·
电气工程
✓ 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）