MATERIALS LETTERS
·
2022
·
IF 3.574
Jinke Song,Guangyue Shi,Xiaoting Song,Zidong Zhang,Yao Liu,Runhua Fan
Composites with negative permittivity behavior have brought about widespread attention for their broad application prospects in electromagnetic field or being used for novel capacitance. In this work, multiwall carbon nanotubes/polyvinylidene fluoride (MWCNTs/PVDF) composites with gradually increasing MWCNT filling content were prepared by hot-pressing in order to acquire negative permittivity. The microstructure, ac conductivity, and real permittivity of the samples were elaborated. As MWCNTs content increases, the percolation phenomenon occurs accompanied by the conversion of conductive mechanism from hopping conduction to free electron conduction. It’s found that negative permittivity property was obtained at a lower filler content and can be regulated by controlling MWCNTs content, which is related to the plasma oscillation state of free electrons in MWCNTs.
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
高影响因子
Results in Physics
·
2017
·
IF 0.946
Qingguo Chi,Guang Liu,Changhai Zhang,Yang Cui,Xuan Wang,Qingquan Lei
In this paper, the 0.5Ba(Zr 0.2 Ti 0.8 )O 3 -0.5(Ba 0.7 Ca 0.3 )TiO 3 nanofibers (BZT-BCT NFs) with high aspect ratio were synthesized by electrospinning technique, and the PVDF-based composites filled with the BT NPs or BZT-BCT NFs were fabricated. Obviously, compared to the BT NPs/PVDF composite, the dielectric properties of BZT-BCT NFs/PVDF composites are improved at given volume fraction. The electric modulus formalism indicated that the BZT-BCT NFs could effectively enhance the interfacial polarization of the BZT-BCT NFs/PVDF composites than that of the BT NPs/PVDF composite. In addition, the BZT-BCT NFs with large aspect ratio can make the composites polarize at a higher field strength, thus the composites obtain higher polarization strength. The energy density of 3 vol% BZT-BCT NFs/PVDF composite is 3.08 J/cm 3 at 240 kV/mm, which is 2.01 times higher enhancement than the BT NPs/PVDF composite (1.53 J/cm 3 at 180 kV/mm). These results also provide a simple but effective method to achieve the materials with high capacitance for energy storage.
研究领域:
材料科学
·
电介质物理
✓ 已验证
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 102
·100585-100589
·
IF 3.289
Haibo Yang,Ning Han,Ying Lin,Ge Zhang,Lei Wang
Polyaniline/CoFe2O4/polyvinylidene fluoride (PANI/CoFe2O4/PVDF) composites were synthesized by an in situ polymerization method. The electromagnetic data demonstrate that the PANI/CoFe2O4/PVDF composite exhibit an excellent microwave absorption in the range of 2.0–18.0 GHz. The maximum reflection loss (RL) value can reach −57.7 dB at 7.6 GHz with a thickness of 4 mm and the absorption bandwidth with the RL below −10 dB is up to 3.4 GHz (from 6.5 to 9.9 GHz), which indicates that the microwave absorbing properties of the PANI/CoFe2O4 composite can be enhanced by the introduction of PVDF and the PANI/CoFe2O4/PVDF composite has potential applications for high-efficient microwave absorbers.
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2024
·
IF 8.4
Xiao Kong,Qi-Zheng Wang,Ye-Fei Wang,Hao-Ming Huo,Fang-Qi Kou,Shu-Bo Zhang,Jun Zhao,Dan Zhang,Liang Hao,Yan-Jiao Chang,Dong-En Zhang
Improving the content of polar crystal phase and the hydrophilicity of PVDF membranes are proved the efficient ways to improve the enduringly anti-fouling ability of PVDF membranes. But synergistic manipulating the polymorphic structure and hydrophilicity of PVDF membranes is rarely reported so far. In this paper, the in-situ esterification reaction between styrene-maleic anhydride (SMA) and meglumine (MG) during nonsolvent induced phase separation (NIPS) process is found to simultaneously manipulate the polymorphic structure and hydrophilicity of PVDF membranes. The water contact angle of membranes is largely reduced from 95.8° to 31.2° with the increase in the MG adding amounts, proving that the hydrophilicity of PVDF membranes is notably improved. Moreover, the β-phase content is improved as the MG adding amounts increase due to the enhanced interactions between the –OH groups and the –CF 2 groups of PVDF through hydrogen bonds. As a result, a highly hydrophilic PVDF membrane with >90 % β-phase content is obtained. The durable antifouling testing reveals that the PVDF blend membranes possess lower flow decline ratio and higher flux recovery ratio compared with the virgin PVDF membranes, thus exhibiting better antifouling ability. The synergistic manipulation of hydrophilicity and crystalline phase of PVDF membranes might offer a paradigm shift in the design of high-performance separation membranes.
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
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
·
2024
·
IF 5.9
Shixiong Chen,Jiarong Wang,Jing Zhang,Qinghao Zeng,Hong Jiang,Haiqing Chang,Tian C. Zhang,Xiaobao Tian,Kai Wang,Ying Liang
Surface modification could remarkably improve the oil–water separation ability of membrane, but suffers from limited survival positive effect layer after long-term operation. Herein, we report a systematic comparative study between bulk and surface modification (i.e., synchronous or sequential electrospun/elecrospraying) on hydrophobic polyvinylidene difluoride (PVDF) membrane. A hydrophilic UiO-66-NH 2 @polyacrylic acid micro/nanospheres (UiO@PAA) was selected as functional layer to improve the separation and adsorption capability of PVDF. The surface modification (SMM) and bulk modification membranes (BMM) exhibited the similar water wetting behavior in air as the same surface layer. The spider filament-like nanofibers of BMM could enhance the mechanical stability and dispersion uniformity of active sites among the PVDF fibers. In terms of oil-in-water emulsions separation ability, the BMM was superior to the SMM with the maximumly increase of separation efficiency and filtration flux to 1.3 % and 192.6 L m -2 h −1 , respectively. As for dye absorption, the BMM showed better adsorption capacity with a removal efficiency over 96 %. For the low concentration of methylene blue, the removal efficiency of SMM was only 94 %, while the removal efficiency of the BMM reached 98 % at room temperature. In addition, the BMM exhibited higher removal efficiency over 94 % compared with that less than 84 % of SMM after eight cycling tests, confirming its advantages in repeatability. This study demonstrates that the bulk modification can endow the initial membrane with better performance and durability, showing more promising prospects in actual wastewater treatment.
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
BIOSENSORS & BIOELECTRONICS
·
2025
·
IF 10.5
Tao Jing,Yaolei Zhang,Zhongtao Li,Xinyu Tao,Xiong Xiong,Chaoming Xie,Weili Deng,Feng Lin,Hongyu Sun,Shuxin Qu
Monitoring cardiac rhythm is crucial for diagnosis of heart failure. However, the deficient sensitivity of polyvinylidene fluoride (PVDF) sensors impede their application in monitoring of cardiac rhythm due to the limited piezoelectricity. Here, doping of CoFe 2 O 4 and aligning fibers were jointly adopted to enhance the piezoelectricity of PVDF, attributed to the transformation of α-PVDF to β-PVDF from 51.54 to 82.36 % confirmed by FTIR and First Principles simulation. Then the higher sensitivity piezoelectric sensors were developed based on aligned PVDF/CoFe 2 O 4 accompanying with the superior frequency characteristics, rapid response, endurance stability, permeability and self-cleaning capabilities, compared to that of random PVDF/CoFe 2 O 4 and PVDF sensors, which were 17.28, 13.40 and 2.16 mV kPa −1 , respectively. Thus, the sensitivity of PVDF/CoFe 2 O 4 sensors was sufficient to distinguish the variations of cardiac rhythm or arrhythmia of the established and verified heart failure rat model, including amplitude, cycle and frequency. The notable characteristic of an evolving heart failure was the significantly decreased amplitude initially, followed by a dramatic drop in the cycles of cardiac impulse. Hence, this non-invasive method is promise in providing valuable warning signs for predicting heart failure based on aligned PVDF/CoFe 2 O 4 sensors, as well as in the prevention its occurrence.
研究领域:
生物医学工程
·
心血管疾病
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Frontiers in Materials
·
2025
·
IF 2.9
Liwu Fu,Jiangfeng Hu,Peng Luo,Dong Xiang,Wenying Hui,Lei Cheng,Yan Zhou,Xiong Zhengrong,Dengzun Yao,Xianghai Jing
The white weathering layer materials that can effectively block the entire solar light band is of great importance for improving the service life, safety, and reliability of the materials. In this work, CsxWO3@PDA was prepared by in situ polymerization to achieve high absorption in the full spectral range and increase the compatibility between CsxWO3 particles and polyvinylidene fluoride (PVDF). PVDF composite films with different particle contents were prepared through compounding with titanium dioxide (TiO2) and CsxWO3@PDA. The prepared composite films were characterized by FT-IR, field emission scanning electron microscopy, universal material testing machine, whiteness meter, and ultraviolet visible spectroscopy. The results showed that the CsPVDF composite films with CsxWO3@PDA and TiO2 exhibited a whiteness level higher than 74, a transmittance of less than 5% in the wavelength range of 200–2500 nm, and a transmittance close to zero in the range below 1750 nm, demonstrating excellent shielding effect. The xenon lamp aging test also confirmed that the composite films had excellent weather resistance after aging 500 h. At the same time, adding a certain amount of CsxWO3@PDA could improve the tensile strength of PVDF.
研究领域:
材料科学
·
聚合物工程
✓ 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
Rui Zhang,Yu Li,Youfeng Cai,Qiong Han,Tongqing Zhang,Yi Liu,Kunling Zeng,Chen Zhao
Silver-phosphate/graphene oxide/APTES (Ag 3 PO 4 /GO/APTES) composite materials modified by 3-aminopropyltriethoxysilane (APTES) were incorporated into polyvinylidene fluoride (PVDF) membrane to obtain light catalytic membrane. The structure and morphology of Ag 3 PO 4 /GO/APTES were characterized by Fourier transform infrared (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and thermogravimetric analyzer (TGA). Next, the morphology structure and roughness of Ag 3 PO 4 /GO/APTES/PVDF membrane were studied using SEM and Atomic force microscopy (AFM). The hydrophilicity and water flux of blended membranes were enhanced by the presence of a large number of hydrophilic groups on the surfaces of GO and APTES. Using Bovine serum albumin (BSA) solution as a pollution model, the multi-cycle anti-organic pollution ability of composite membranes was explored, and the anti-pollution performance was improved. The results showed that with the increase of Ag 3 PO 4 /GO/APTES content in the composite membrane, the rejection rate of dyes increases significantly. The enhanced photocatalytic degradation can be attributed to the presence of RGO which facilitates electron mediation and shuttle. This work provide a method for the efficient removal of dyes from wastewater.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
Journal of Inorganic and Organometallic Polymers and Materials
·
2019
·Vol. 29
·期 5
·1625-1636
·
IF 1.637
Zhang Rui,Zhu Xuyang,Liu Yi,Cai Youfeng,Han Qiong,Zhang Tongqing,Li Yu
In this work, the versatile filler (HNTs) consisted of a halloysite nanotube as skeleton and intermediate magnetic nanoparticles coating poly(dopamine + 3-aminopropyltriethoxysilane) derivate layer were prepared. PVDF membranes were then manufactured by incorporating a series of ratios of HNTs. The Fourier-transform infrared (FT-IR), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and transmission electron microscope (TEM) results proved that the modified materials were successfully achieved. The morphologies of membranes were characterized by scanning electron microscope (SEM) and atom force microscope (AFM). Meanwhile the PVDF hybrid membranes exhibited a stronger hydrophilicity (contact angle is 53°), higher bovine serum albumin (BSA) rejection (99%) than pure membrane (87°and 54%), and hybrid membranes maintain a higher flux recovery rate (FRR) that attains 85.3% after two cycles. Besides, the composite membrane showed a good removal rate (97.2%) of methylene blue. According to above experimental parameters, the 6% (based on PVDF mass) HNTs composite membrane was defined as the experimental optimal selection, and it could provide a promising candidate for methylene blue solution separation.
研究领域:
材料科学
·
环境工程
·
纳米技术
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED PHYSICS
·
2015
·Vol. 117
·期 8
·
IF 2.183
He Hongcai,Luo Feifei,Qian Neng,Wang Ning
Three-phase composites of poly(vinylidene fluoride)-BaFe 12 O 19 -reduced graphene oxide (PVDF–BFO-RGO) were synthesized by a facile wet chemical method and hot-pressing approach. The phase structure, topography of the hybrid materials were characterized by X-ray diffraction, scanning electron microscopy, and Raman spectra. Influence of RGO on their electromagnetic properties was investigated. Especially, improved microwave absorption and electromagnetic properties of BaFe 12 O 19 –PVDF composites by incorporating RGO were obtained and studied. The PVDF/BFO/RGO sample with m(RGO):m(BFO) = 5:100 shows the best microwave absorption properties with a minimum RL = −32 dB at 11 GHz and with the bandwidth less than −20 dB from 9.6 to 12.8 GHz. The composites were believed to have potential applications as the microwave absorber.
研究领域:
材料科学
·
物理学
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2024
·
IF 8.4
Weiguo Kong,Longfei Zhang,Na Yang,Bin Jiang,Luhong Zhang,Yong Liu
Rational design of hydrophilic hierarchical structures on the membrane surface is a promising method to improve oil/water separation efficiency. However, oil droplets with intrinsic adhesion tend to accumulate on the membrane surface, which deteriorates membrane performance. In this study, tannic acid-Zn(II) complex was homogeneously anchored on the PVDF membrane surface and further in situ converted to ZIF-8 in the presence of 2-methylimidazole. Subsequently, Cu ion exchange was employed to transfer ZIF-8 layer to gerhardtite (Cu 2 (OH) 3 NO 3 ) with a hierarchical structure. Accordingly, the as-prepared PVDF/TA-gerhardtite membrane possessed attractive hydrophilicity and underwater superoleophobicity with oil contact angles above 150°, therefore achieving over 98 % oil rejection towards various surfactant stabilized oil-in-water emulsions. Moreover, self-cleaning properties can be realized by activating peroxymonosulfate, and 97 % of tetracycline hydrochloride, the target pollutant, was degraded within 30 min owing to the generation of sulfate radicals and hydroxyl radicals. Due to the attractive hydrophilicity and catalytic oxidation capacity of the gerhardtite hierarchical structure, degradation and bubble generation induced fouling recovery was accomplished after PMS cleaning, and the irreversible fouling decreased to 2.2 % after consecutive soybean oil fouling. Therefore, this work provides new insights into the construction of hierarchical structures on membrane surfaces and demonstrates their potential applications in oil/water separation and fouling mitigation.
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
Nanomaterials
·
2025
·Vol. 15
·期 4
·279
·
IF 4.3
Yuning Li,Xinya Wang,Weiqiu Huang,Xufei Li,Ping Xia,Xiaochi Xu,Fangrui Feng
Membrane technology has been widely used in industrial CO2capturing, gas purification and gas separation, arousing attention due to its advantages of high efficiency, energy saving and environmental protection. In the context of reducing global carbon emissions and combating climate change, it is particularly important to capture and separate greenhouse gasses such as CO2. Zr-MOF can be used as a multi-dimensional modification on the polymer membrane to prepare self-assembled MOF-based mixed matrix membranes (MMMs), aiming at the problem of weak adhesion or bonding force between the separation layer and the porous carrier. When defective UiO-66 is applied to PVDF membrane as a functional layer, the CO2separation performance of the PVDF membrane is significantly improved. TUT-UiO-3-TTN@PVDF has a CO2permeation flux of 14,294 GPU and a selectivity of 27 for CO2/N2and 18 for CO2/CH4, respectively. The CO2permeability and selectivity of the membrane exhibited change after 40 h of continuous operation, significantly improving the gas separation performance and showing exceptional stability for large-scale applications.
研究领域:
材料科学
·
环境科学
✓ 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）