COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2022
·
IF 5.518
Ziqiang Liu,Yunfeng Wu,Fengxia Lan,Gaoyi Xie,Mengchen Zhang,Chunping Ma,Jianbo Jia
Hydration is critical to restricting surface fouling in membrane separation processes. In order to tightly coat hydrophobic membrane surfaces with zwitterions that afford excellent hydration ability, herein, a facile strategy combining copolymer design and dopamine-assisted co-deposition was described. Three copolymers containing dopamine methacrylamide (DMA) unit and 2-methacryloyloxyethyl phosphorylcholine (MPC) unit, with/without a third hydrophilic unit, were synthesized via free radical polymerization , and characterized by 1 H nuclear magnetic resonance ( 1 H NMR) spectroscopy, Fourier-transform infrared (FTIR) spectroscopy and gel-permeation chromatography (GPC). Subsequently, the as-synthesized copolymers were co-deposited with dopamine hydrochloride on polyvinylidene fluoride (PVDF) membrane surfaces. X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), atomic force microscopy (AFM) and water contact angle (WCA) measurements were conducted to analyze the superficial chemical composition , morphologies, roughness and hydrophilicity of the membranes. Systematical filtration and antifouling experimental investigations showed that the zwitterionic-copolymer-modified membranes demonstrated high permeate fluxes, good rejection performance, and great antifouling properties, attributing to the enhanced hydrophilicity of the membrane surfaces. Especially, the p(DM)/PDA-PVDF modified membrane exhibited outstanding water flux of 192.5 L·m −2 ·h −1 and ideal BSA rejection of 96.1 % with excellent flux recover ratio ( FRR 1 : 82.6 %, FRR 3 : 97.8 %). This work presents a feasible hydrophilic modification strategy of hydrophobic membranes, which is expected to provide a new avenue to overcome the permeability-selectivity trade-off limitations and fouling problems in membrane separation processes.
✓ 已验证
DOI
高影响因子
SENSORS AND ACTUATORS A-PHYSICAL
·
2022
·
IF 4.291
Bin Zhou,Yu Chen,Kun Hu,Shah Fahad,Yu-xuan Zhou,Yi-ming Yuan,Min Wang
Flexible pressure sensor array has attracted much attention in wearable electronics , but still lacks self-power, high resolution, large-area fabrication, and low crosstalk . Herein, we present a self-powered pressure sensor array via patterned piezoelectric polyvinylidene fluoride-trifluoroethylene (PVDF-TrFE) nanofibrous. The PVDF-TrFE nanofibers were collected by patterned metal ground electrodes that isolated each piezoelectric cell. The isolated sensing cells can effectively reduce the crosstalk caused by additional deformation. The potential from individual cell is detected through the row+column electrode configuration to determine the corresponding pressure point and trajectory information. The as-fabricated pressure sensor array showed an excellent linear piezoelectric response (2.5 mV/kPa), a fast response time (5 ms), and good repeatability (25,000 cycles). Furthermore, our piezoelectric devices with constructed PVDF-TrFE layer are feasible in scaling up to a large-area sensor array. Accurate recognitions of the letter "h" trajectory tracking and tactile sensation by our self-powered tactile sensor array show potential applications in electronic skin and artificial intelligence.
✓ 已验证
产品关联
DOI
高影响因子
POLYMER
·
2022
·
IF 4.432
Lu Jing,Weili Li,Chang Gao,Menglu Li,Jun He
Polymer dielectrics with high permittivity have bright prospect in the fields of electric stress control, portable devices and micro-electronics. In this paper, high-entropy oxide (Eu 0.2 Bi 0.2 Y 0.2 La 0.2 Cr 0.2 ) 2 O 3 (EBYLCO) nanofiber and BiFeO 3 (BFO) nanofiber were successfully fabricated and incorporated into P(VDF-HFP) matrix. The dielectric performance was comprehensively investigated at room temperature and high temperature. Furthermore, the white-light illumination experiment was performed to prove the important effect of the high-entropy oxide on dielectric properties . At a low filling content, EBYLCO-P(VDF-HFP) nanocomposite achieves a relatively high permittivity compared with many previous literatures. This is mainly attributed to the novel structure of high-entropy oxide with a narrow energy bandgap, which makes it easier to separate electrons and holes, and thus leads to a stronger light response and a more obvious dielectric response. Moreover, the experimental results prove that the interfacial polarization in EBYLCO-P(VDF-HFP) nanocomposite is stronger than that of BFO–P(VDF-HFP). This work has great value and provides a new strategy of the filling selection for the high dielectric nanocomposites.
✓ 已验证
产品关联
DOI
高影响因子
NANOTECHNOLOGY
·
2022
·Vol. 33
·期 42
·425601
·
IF 3.953
Wenwu Jiang,Yi Han,Yanhuai Ding
Electrospun PAN/PVdF-HFP membranes have the potential to be used as separators for Li-ion batteries owing to their good mechanical properties and high chemical stability. However, the application of PAN/PVdF-HFP separators has been hampered by their poor electrochemical performances. In this study, semi-aligned PAN/PVdF-HFP nanofiber separators have been fabricated by an electrospinning technology. Sepiolite and ZIF-67 co-modification was employed to enhance the physical properties of the PAN/PVdF-HFP separators. The test cells with the as-prepared composite separator showed better electrochemical performance than the commercial and raw PAN/PVdF-HFP separators.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Electronic Materials
·
2022
·
IF 4.494
Cheng Han,Lirong He,Qi Wang,Chuhong Zhang
Three-dimensional (3D) printing technologies possess incomparable advantages in fabricating 3D piezoelectric devices, enhancing the mechanical-to-electrical conversion efficiency. Among them, direct ink writing (DIW) holds great promise in constructing piezoelectric polymer devices as it enables self-polarization benefiting from the alignment of dipoles induced by the high pressure during the printing process. Besides, the electroactive phase of piezoelectric polymers is retained due to the operation is under ambient conditions. However, for the generally applied solvent-evaporation-assisted DIW technique, the architected structure suffers from drastic shrinkage and warpage in the final parts, which ultimately leads to a significant deviation from the programmed measure. In this work, for the first time, we develop a solvent-exchange-assisted DIW printing strategy to architect accurate and stable 3D PVDF PEH. This solvent exchange process in water not only enables the complete retaining of filament measure and generation of micropores to amplify the stain but also promotes the PVDF crystallization and formation of the β-phase. Moreover, trace vitamin B2 is formulated into the ink, affording self-polarized high β-phase content (95%) PVDF with good printability and optimal storage modulus to hold the 3D shapes. As a result, the 3D printed PVDF delivers an output voltage of 17.8 V, increased by 304% compared with device fabricated by solvent-evaporation-assisted DIW technique, and an impressive area output voltage density (11.04 V cm–2) which is twice that of the reported DIW printed PVDF PEH. This facile approach demonstrates a potential roadmap to high performance PEH through exploring complex 3D geometries enabled by the solvent-exchange-assisted 3D printing technique.
✓ 已验证
产品关联
DOI
高影响因子
Polymers
·
2022
·Vol. 14
·期 16
·3294
·
IF 4.967
Han Wang,Yiliang Bao,Xiuding Yang,Xingzi Lan,Jian Guo,Yiliang Pan,Weimin Huang,Linjun Tang,Zhifeng Luo,Bei Zhou,Jingsong Yao,Xun Chen
At present, the situation of air pollution is still serious, and research on air filtration is still crucial. For the nanofiber air filtration membrane, the diameter, porosity, tensile strength, and hydrophilicity of the nanofiber will affect the filtration performance and stability. In this paper, based on the far-field electrospinning process and the performance effect mechanism of the stacked structure fiber membrane, nanofiber membrane was prepared by selecting the environmental protection, degradable and pollution-free natural polysaccharide biopolymer pullulan, and polyvinylidene fluoride polymer with strong hydrophobicity and high impact strength. By combining two kinds of fiber membranes with different fiber diameter and porosity, a three-layer composite nanofiber membrane with better hydrophobicity, higher tensile strength, smaller fiber diameter, and better filtration performance was prepared. Performance characterization showed that this three-layer composite nanofiber membrane had excellent air permeability and filtration efficiency, and the filtration efficiency of particles above PM 2.5 reached 99.9%. This study also provides important reference values for the preparation of high-efficiency composite nanofiber filtration membrane.Keywords:electrospinning;biopolymer;composite structure;air filtration;nanofiber membrane
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Chuanfeng Zang,Xiangye Han,Hao Chen,Haifeng Zhang,Yonggang Lei,Hongchao Liu,Chunxia Wang,Guangyu Zhang,Mingzheng Ge
ZnO has been widely employed in the photodegradation of pollutants; however, it exhibits poor photocatalytic performance under visible light illumination. Thus, visible-light-driven heterostructured PVDF/ZnO/Ag 2 O photocatalysts were fabricated by combining the electrospinning, hydrothermal, and in situ deposition techniques. As matrix materials, it is easy to recycle and reuse electrospun PVDF nanofibers . ZnO nanorods anchored on PVDF nanofibers with a high specific surface area provide an abundance of photocatalytically active sites. As a photosensitizer , silver oxide nanoparticles enhance the visible-light photocatalytic efficiency. Thus, the composited PVDF/ZnO/Ag 2 O photocatalysts exhibit excellent photocatalytic performance under both UV and visible light irradiation as a result of the enhanced electron-hole separation/transfer and broadened visible light absorption range. Under visible light irradiation, the kinetic constant of PVDF/ZnO/Ag 2 O nanocomposites is 24.4 and 6.73 times greater than that of PVDF/Ag 2 O and PVDF/ZnO, respectively. Moreover, the PVDF/ZnO/Ag 2 O nanocomposites exhibit advantages in recycling and reusing with high stability, thus considerably widening their practical applications in the field of environmental remediation.
✓ 已验证
产品关联
DOI
高影响因子
POLYMER TESTING
·
2022
·
IF 4.931
Yijun Fu,Yue Cheng,Chi Chen,Dawei Li,Wei Zhang
The effect of hydrothermal process on the morphology and piezoelectric performance of zinc oxide/polyvinylidene fluoride (ZnO@PVDF) composite nanofibers is rarely studied. In this work, highly aligned ZnO nanorods were epitaxially grown on the electrospun PVDF nanofibers to form ZnO@PVDF composite nanofibers with a pine-needle-like bionic structure. Nanofibers before and after hydrothermal reaction were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and piezoelectric analysis. Results demonstrated that hydrothermal reaction conditions, including mass ratio of ZnCl 2 to HMTA, ammonium hydroxide volume, hydrothermal reaction time and temperature should be carefully controlled and cooperated with each other to produce ZnO nanorods with ideal microstructure and piezoelectric performance. FTIR and XRD results confirmed the transformation of β phase in PVDF nanofibers from α phase in PVDF powder due to the elongation under strong electric field during electrospinning. Results of SEM and XRD certified the successful growth of ZnO nanorods with hexagonal wurtzite structure, which plays an important role in facilitating the percentage of β phase and the resulted piezoelectric capacity of ZnO@PVDF composite nanofibers. All of these characterizations suggest that the proposed pine-needle-like ZnO@PVDF composite nanofibers demonstrate promising potential in the wide application of electromechanical energy conversion.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2022
·
IF 14.224
Mengnan Chai,Wangshu Tong,Zhihao Wang,Zhensheng Chen,Yuancheng An,Yihe Zhang
Piezocatalysis driven by a gentle force possesses broad application prospects for degrading organic pollutants , sterilisation, wound healing and tissue recovery. The flexible and industrially scalable poly(vinylidene fluoride) (PVDF) film is commonly used in piezocatalysis. However, under gentle force action, PVDF composite-based piezocatalysis is poor. Herein, a flexible porous film based on poly(vinylidene fluoride)-hexafluoro propylene (PVDF-HFP) is enhanced with Fenton fillers (α-Fe 2 O 3 nanoparticles). α-Fe 2 O 3 nanoparticles improve the piezoelectric catalysis performance of PVDF-HFP by the β-phase enhancement and provide Fe 3+ to react with H 2 O 2 generated by the piezoelectric film itself, leading to an additional Fenton reaction . Meanwhile, the Fe 3+ /Fe 2+ cycle in the Fenton process accelerates under the piezoelectric field, promoting the Fenton reaction for 6.9% degradation improvement. The study on Fe 2 O 3 /PVDF-HFP porous film with the piezo–Fenton reaction under flowing water may help promote new piezocatalysis designs with high efficiency for self–powered environmental purification.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2022
·Vol. 33
·期 7
·3965-3981
·
IF 2.779
Ahmed Arsalan,Jia Yunming,Deb Hridam,Arain Muhammad Fahad,Memon Hafeezullah,Pasha Khalid,Huang Yi,Fan Qinguo,Shao Jianzhong
The use of piezoelectric materials has been increased due to the growing demand for wearable devices. Herein, we report the development of new copolymer poly (vinylidene fluoride-co-trifluoroethylene) (PVDF-TrFE)-based reduced graphene oxide (rGO) and multiwalled carbon nanotubes (MCNTs) loaded electrospun (E-Spun) nanofibers. The rGO-MCNTs loaded PVDF-TrFE nanofibrous mat led to the fabrication of ultra-sensitive piezoelectric pressure sensors for potential wearable health monitoring applications. The doped PVDF-TrFE solution of different weight percentages of rGO-MCNTs as fillers was prepared and used to fabricate an e-spun nanofibrous mat. Complete characterization of resultant materials were carried through diverse instruments which reveals the successful integration of rGO-MCNTs (3.2%) as a dopant that improved the β-phase up to 92%. The DSC analysis further exposes the high thermal stability of the PVDF-TrFE nanofibers mat due to the enhanced crystallinity with the addition of nanofillers. The newly developed sensor’s overall output (based on sensitivity) was calculated under a variable applied pressure range of 0.25 ~ 300 cN at 50 HZ. Results show that the pressure sensor response has improved from 16.125 ~ 0.430 kPa −1 , corresponding to a higher sensitivity under static and dynamic forces in the applied pressure range. These results are of a fundamental study and open new prospects for the hybrid nanofibrous mat as alternative electrode material in the piezoelectric pressure sensor.
✓ 已验证
产品关联
DOI
高影响因子
DALTON TRANSACTIONS
·
2023
·Vol. 52
·期 33
·11441-11450
·
IF 4
Defeng Hu,Zhongqiao Sun,Yide Han,Hao Meng,Xia Zhang
Considering the surface affinity of MOFs and separation advantages of polymer membranes, herein, a one-step interface synthesis strategy is used in the construction of Cu-BTC/PVDF hybrid membranes, in which Cu2+ ions and 1,3,5-benzenetricarboxylic acid (H3BTC) were dissolved in ionized water and n-octanol separately, and polyvinylidene fluoride (PVDF) films were laid at the interface of two immiscible solvents. As a result, Cu-BTC was generated and readily self-assembled inside the PVDF films. Scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA) and the Brunauer–Emmett–Teller (BET) method were used to characterize Cu-BTC/PVDF hybrid membranes, and Congo red (CR) was selected as the target dye to evaluate the surface adsorption activity of the hybrid membranes. Batch adsorption tests under various conditions were conducted to optimize the adsorption capacity, adsorption kinetics, isotherms and thermodynamics, which were analyzed to further explore the adsorption behavior. Based on this, the adsorption mechanism was discussed. It is worth noting that because of the π–π stacking interaction and hydrogen bonding, an extraordinary adsorption capacity of CR was achieved, and the good separation advantage and the cyclic adsorption performances endow the resulting Cu-BTC/PVDF hybrid membranes with promising applications in the removal of organic dyes from practical wastewater.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2021
·
IF 8.742
Tao Zhang,Xin Guo,Brusly Solomon,Mohsen Sharifpur,Li-Zhi Zhang
Hollow fiber membrane-based humidification-dehumidification desalination of seawater is a low-carbon freshwater-harvesting technology that can be powered by low-grade solar energy. Polyvinylidene fluoride (PVDF) can be easily fabricated into membranes and is considered the most promising material for industrial seawater desalination. However, membrane fouling and wetting have always been major obstacles with this technology. In this study, a hydrophobic-hydrophilic MXene/PVDF composite hollow fiber membrane (PVDF-MP) with remarkable antiwetting and antifouling properties was successfully prepared using a chemical grafting method. The interfacial dehydration reaction between the hydrophilic substrate layer (PVDF-OH) and the hydrophobic skin layer (MXene-P [MP]) was verified by Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy, and a detailed reaction mechanism was provided. The hydrophilic substrate layer decreased moisture transfer resistance, while the hydrophobic skin layer reduced the membrane surface energy and increased the surface roughness . This resulted in a contact angle of 156.2°, which was measured using a new method that accounted for the curvature of the membrane. The superhydrophobic surface possessed a strong repulsive force toward water, and the air gap between the water and membrane impeded pollutant deposition on the inner surface of the membrane. Moreover, the rough surface created high entry pressure and prevented water from entering the membrane pores. Thus, the permeate flux of the PVDF-MP membrane persisted over 120 h during desalination tests, surpassing the performance of traditional materials.
✓ 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）