MICROPOROUS AND MESOPOROUS MATERIALS
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2024
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IF 4.8
Changfeng Zeng,Jie Li,Jie Gong,Lixiong Zhang,Liang Yu
ZIF-8/PVA microspheres with an even size were synthesized with the assistance of a simple microfluidic device. The ZIF-8/PVA microdroplets were first generated in a simple co-flow microfluidic device using a PVA aqueous solution dispersed with ZIF-8 nanoparticles as the dispersed phase and fatty acid methyl ester (FAME) as the continuous phase. Subsequently, the ZIF-8/PVA microdroplets were further extracted to form ZIF-8/PVA microspheres. The influence of the type of continuous phase on the sphericity of microspheres was investigated and the effect of ZIF-8 content was studied. Further studies showed that decreasing the extraction rate and using additives of NaCl in the dispersed phase could improve the sphericity of the ZIF-8/PVA microspheres. Finally, the synthesized ZIF-8/PVA microspheres were used to study the loading and release of tetracycline. The results showed that the loading of ZIF-8/PVA microspheres was more than 5 times higher than that of pure PVA microspheres. The drug release time of ZIF-8/PVA microspheres was much longer than that of the PVA microspheres and the release rate was significantly affected by the pH of the environment.
研究领域:
材料科学
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药学
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产品关联
DOI
高影响因子
OPTICAL MATERIALS
·
2024
·
IF 3.8
Cheng Cheng,Zhaokang Zheng,Aiwu Wang
Photochromic smart windows allow for simple manufacturing without the need for additional energy input for adaptive control of sunlight, which will have a huge impact on the comfort of daylight and the development of smart windows. Among them, although molybdenum-based materials have advantages such as low cost and stable coloring, the lack of fast transmission switching capability and liquid phase color changing environment limit its implementation in the field of smart windows. Here, we report a low-cost method to fabricate a novel photochromic hydrogel (MoOx/PVA) by combining molybdenum oxide nanosheets (MoOx, 2 ≤ x ≤ 3) with polyvinyl alcohol (PVA) gel. Under ultraviolet light (UV = 360–400 nm) irradiation, the hydrogel achieves rapid color change visible to the naked eye within 10 s, with an exponential decrease in transmittance, reversible switching of transparency between 70 % and 5 %, and retains about 95 % transmittance after 14 cycles. Due to the good biocompatibility of molybdenum oxide, hydrogel can also be used for personal wearable, which can achieve 1.4 °C of cooling when exposed to sunlight for 3 min. Moreover, the photochromic and recovery properties of the large-sized (29.7 cm × 21 cm) MoOx/PVA hydrogel demonstrate its broad prospects for production applications in smart windows. It is believed that this study will open new opportunities for both fabrication and application in photochromic smart windows and intelligent devices.
研究领域:
材料科学
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光电技术
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纳米技术
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智能材料
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产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
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2019
·Vol. 43
·期 12
·4815-4822
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IF 3.069
Jin Wang,Mengde Deng,Yahui Xiao,Wentao Hao,Chengfeng Zhu
Polyelectrolytes with good ionic conductivity and dielectric properties have been shown to be superior for supercapacitors and other power storage devices. Here, a cationic polyelectrolyte with blended poly(N-vinylpyrrolidone-co-diallyl dimethyl ammonium chloride) (P(NVP-co-DMDAAC)) copolymer and poly(vinyl alcohol) (PVA) was prepared via the interpenetrating polymer network (IPN) technique. The dielectric properties, ionic conductivity, mechanical properties and the influence of the thicknesses of hydrogel membranes on capacitance properties were studied. The introduction of the cationic DMDAAC monomer and polar PVA increased the integrated performance of the PNVP hydrogel. In comparison with PVA, PNVP, and P(NVP-co-DMDAAC), P(NVP-co-DMDAAC)/PVA IPN hydrogel exhibited higher permittivity of 27.19 at 1 kHz frequency and the maximum ionic conductivity of 3.66 × 10−2 S cm−1 at 10% PVA dosage. The tensile strength increased with the increase in the PVA content. The specific capacitances of P(NVP-co-DMDAAC)/10PVA increased with the decrease in the thickness of the hydrogel membrane and its retention rate was 95% after 1000 cycles.
研究领域:
材料科学
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电化学
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能源存储
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产品关联
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
·
2022
·
IF 5.546
Li He,Dezhan Ye,Sen Weng,Xiancai Jiang
Conductive hydrogels have attracted great interest in the fabrication of flexible strain sensors. However, hydrogel-based strain sensors still have unresolved challenges, such as low mechanical strength, lack of frost resistance, easy dehydration, and non-recyclability, which have largely hindered their application. Herein, the ion-conductive starch/PVA/EG/TA/CaCl 2 (SPETC) composite organohydrogel was prepared by the cyclic freezing-thawing method using starch and PVA as the gel backbone, water and ethylene glycol (EG) as the binary solvent, and Ca 2+ and Cl - as the conducting ions carriers. The SPETC organohydrogel exhibited high mechanical properties and showed excellent environmental stability and frost resistance. SPETC organohydrogel was fully physically cross-linked by non-covalent interactions such as hydrogen bonding and ligand bonding, and these reversible interactions can give the gel good recyclability. Moreover, benefiting from the superior mechanical response, SPETC organohydrogel can be assembled as a flexible wearable strain sensor for real-life motion monitoring.
研究领域:
材料科学
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生物医学工程
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DOI
高影响因子
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
·
2017
·
IF 2.63
Hongjian Wang,Bin Liu,Weilong Huang,Zi Lin,Jie Luo,Yan Li,Lin Zhuang,Wei Wang,Lelun Jiang
A novel approach, continuous needleless electrospinning from the tips of magnetization-induced self-assembling PVA/ferrofluid cone array, was proposed to prepare magnetic nanofibers. A PVA/ferrofluid was synthesized, the needleless electrospinning process was observed, and the morphology and magnetic properties of magnetic nanofibers were investigated. The results showed that the PVA/ferrofluid could remain stable and homogeneous for 21 days under the magnetic field gradient (2.2 mT/mm). “Taylor cone” array of PVA/ferrofluid was self-assembled under both the magnetic and electric fields. As the electric voltage reached 25 kV, the jets were emitted from the “Taylor cone” array, resulting in needleless electrospinning of magnetic nanofibers. Magnetic nanofibers were homogeneous and continuous with an average diameter of 73.6 nm. Magnetic nanofibers showed a good magnetic response property and relatively high saturated magnetization (1.71 emu/g), which is expected to be applied in the biomedical field.
研究领域:
材料科学
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生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2013
·Vol. 131
·期 3
·
IF 1.395
Ting Li,Yuan Ren,Chaohai Wei
Polyvinyl alcohol(PVA) bead crosslinked with boric acid has been widely utilized as a microorganism immobilization carrier. However, it has some disadvantages such as drastic cell viability loss, small adsorption capacity and mass transfer limitation. To improve upon these drawbacks, a new method to prepare PVA composite pieces with the addition of activated carbon (AC) and poly-3-hydroxybutyrate(PHB) was explored through a combination of freezing/thawing and the boric acid method and by using Tween-80 to improve the mass transfer performance of hydrophobic organics. m -Cresol and pyrene were used as representative compounds with benzene ring structures to model hydrophilic and hydrophobic organics in order to test the performance of PVA pieces. The results showed that, compared with the boric acid method alone, a combination of freezing/thawing and the boric acid method led to a decrease in total organic carbon(TOC) loss from 0.315 g g −1 to 0.033 g g −1 and increased the oxygen uptake rate(OUR) of microorganisms from 0.03 mg L −1 ·min −1 to 0.22 mg L −1 min −1 . The m -cresol equilibrium adsorption amount of the PVA-SA(sodium alginate)-PHB-AC piece was 2.80 times that of the PVA-SA piece. The diffusion coefficient of pyrene in the PVA-SA-PHB-AC piece increased from 0.53×10 −9 m 2 min −1 to 2.30×10 −9 m 2 min −1 with increasing concentrations of Tween-80 from 1000 mg L −1 to 5000 mg L −1 . The PVA-SA-PHB-AC composite carrier demonstrated great scope for immobilizing microorganisms for practical wastewater bio-treatment. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131 , 39837.
研究领域:
环境科学
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生物工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
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2022
·
IF 10.383
Zongshuai Gong,Silin Zheng,Jin Zhang,Yueqin Duan,Zhiqiang Luo,Fengshi Cai,Zhihao Yuan
Li-organic batteries (LOBs) are promising advanced battery systems because of their unique advantages in capacity, cost, and sustainability. However, the shuttling effect of soluble organic redox intermediates and the intrinsic dissolution of small-molecular electrodes have hindered the practical application of these cells, especially under high operating temperatures. Herein, a cross-linked membrane with abundant negative charge for high-temperature LOBs is prepared via electrospinning of poly(vinyl alcohol) containing halloysite nanotubes (HNTs). The translocation of negatively charged organic intermediates can be suppressed by the electronic repulsion and the cross-linked network while the positively charged Li+ are maintained, which is attributed to the intrinsic electronegativity of HNTs and their well-organized and homogeneous distribution in the PVA matrix. A battery using a PVA/HNT composite separator (EPH-10) and an anthraquinone (AQ) cathode exhibits a high initial discharge capacity of 231.6 mAh g–1 and an excellent cycling performance (91.4% capacity retention, 300 cycles) at 25 °C. Even at high temperatures (60 and 80 °C), its capacity retention is more than 89.2 and 80.4% after 100 cycles, respectively. Our approach demonstrates the potential of the EPH-10 composite membrane as a separator for high-temperature LOB applications.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials Science and Engineering B-Advanced Functional Solid-State Materials
·
2025
·
IF 4.6
Yu Chen,Zhou Luo,Xinyu Shi,Yue Jiang,Yang Zhang,Zhiguang Xu
Liquid metal (LM) is a promising candidate for electromagnetic interference (EMI) shielding due to its exceptional electrical conductivity and ease of processing. However, the high surface tension of LM leads to poor compatibility with polymers, significantly hindering its application in EMI shielding. Here, Al 2 O 3 @LM/borax crosslinked PVA (Al 2 O 3 @LM/BCP) aerogel is prepared using mechanical grinding, melting crosslinking, and directional freeze-drying techniques. The core–shell structure of Al 2 O 3 @LM, prepared by mechanical grinding, effectively reduces the high surface tension of LM, enhancing compatibility with the PVA matrix. Due to its freeze-dried porous structure and superior LM conductivity, the Al 2 O 3 @LM/BCP composite aerogel exhibits outstanding electrical conductivity of 312.5 S/m, efficient electromagnetic interference shielding efficiency (EMI SE) of 80.9 dB, and an excellent SEA/SET ratio of 83.9 %. This work offers a straightforward strategy for developing EMI shielding aerogels with excellent mechanical properties for EMI protection applications.
研究领域:
材料科学
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电子工程
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产品关联
DOI
高影响因子
Environmental Technology & Innovation
·
2021
·
IF 5.263
Yansong Zhang,Zehai Yu,Yunshuang Hu,Caifeng Song,Fuwei Li,Wen He,Xiaofeng Wang,Zhixia Li,Hongfei Lin
Magnetic polyvinyl alcohol–sodium alginate–diatomite (PVA–SA-diatomite) composite carriers for immobilized microorganisms were prepared for removal of NH 4 + -N from effluents. The mass transfer efficiency, chemical stability, and NH 4 + -N removal efficiency of the carriers were investigated. The amount of each ingredient added significantly affected the performance of the carriers. The optimal concentrations of PVA, SA, diatomite , and Fe 3 O 4 were 10%, 1%, 1%, and 2%, respectively. The obtained carrier achieved a NH 4 + -N removal efficiency of 72.5% after reaction for 12 h, which was 31.8% higher than that with the non-magnetic carrier. The removal of NH 4 + -N was attributed to the cooperative action among non-magnetic ingredients, magnetic ingredients, and microorganisms. The adsorptions of NH 4 + -N by non-magnetic ingredients and Fe 3 O 4 contributed 21.2% and 25.5%, respectively, and microorganism metabolism contributed 53.2% to NH 4 + -N removal. The novel texture structure of the carrier leads to improved mass transfer of nutrients and stable activity of microorganisms. Nitrification followed the first-order reaction for low concentration of effluents and zero-order reaction for high concentration of effluents. The reaction rate increased with increasing initial NH 4 + -N concentration. The magnetic carrier was applicable for a long time. These results show the great potential of the developed carrier for industrial applications.
研究领域:
环境工程
·
水处理
·
生物技术
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2023
·
IF 8.2
Sisi Ma,Wenying Shi,Hongbin Li,Yifeng Zhang
Inspired by the natural nacre structure, we propose a new strategy to fabricate mineralized, multiple crosslinked hydrogel membranes with the “rigid silica in soft polymer” nacre-like structure. In-situ SiO 2 nanoparticles (NPs) and polyvinyl alcohol/sodium alginate (PVA/NaAlg) are used to simulate the rigid “bricks” and soft “mortar” compositions of nacre, respectively. The nacre-like mineralized (PVA/CaAlg/SiO 2 ) membrane showed a higher tensile strength of 4.1 ± 0.08 MPa, excellent pure water flux of 170 ± 3 L/m 2 h, and an oil/water rejection rate of 99 %. The interwoven hierarchal structure, similar to nacre, was determined by SEM analysis . In addition, incorporating SiO 2 NPs increases the anti-swelling, roughness, and hydrophilicity of the membranes. PVA/CaAlg/SiO 2 membrane exhibited excellent superhydrophilicity (WCA value was 0°) and superoleophobicity underwater (OCA value was 162°). PVA/CaAlg/SiO 2 membrane also showed excellent separation performance for water-soluble organic pollutants and can be used for dye separation with rejection efficiencies of 99.5 %, 99.1 %, and 98.3 % for Congo red (CR), Alizarin red (AR), and Sunset yellow (SY), respectively. Moreover, PVA/CaAlg/SiO 2 membrane had outstanding long-term filtration and antifouling performance. The biomineralization-inspired structure provides a promising technique that can be used to prepare high-performance organic-inorganic membranes with great promise for wastewater separation application.
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
Journal of Water Process Engineering
·
2022
·
IF 7.34
Lin Chen,Fangqing Li,Longjie Jiang,Fudong He,Yufei Wei
Polytetrafluoroethylene (PTFE) hydrophobic membranes used in direct contact membrane distillation (DCMD) processes were prone to fouling and wetting by oil and surfactants, which hampered their broad industrial application. In this work, a new Janus composite membrane was developed by modifying UiO-66-NH 2 with polyvinyl alcohol (PVA) as a cross-linking agent and immobilizing the modified UiO-66-NH 2 on the PTFE membrane by vacuum filtration. By tuning the ratio of PVA to MOF , an optimally proportioned Janus membrane was obtained, and its performance was tested in DCMD experiments through the use of a sodium chloride feed solution containing hexadecane and sodium dodecyl sulfate. The top layer of this Janus membrane exhibited underwater oleophobicity (130.1 ± 0.96°) and hydrophilicity in the air (54.0 ± 0.92°), while the bottom layer is hydrophobic (132.3 ± 0.97°). Compared to the pristine PTFE membrane, the modified Janus membrane demonstrated promising resistance to both membrane fouling and wetting of oils and surfactants. The desalination rate of 99.99% was still achieved within 24 h with the conductivity remaining lower than 10 μS/cm and the flux maintained at 21.3 L/(m 2 ·h). As a result, the Janus composite membrane developed in this study was shown to be a prospective alternative for treating wastewater containing oily substances and surfactants in a resourceful manner.
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
SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Na Wang,Qilin Liu,Bo Xie,Xuechun Huang,Dan Xiao
Cr(VI) pollution severely threatens the water environment and human health. One of the effective ways to solve this problem is to develop environmentally friendly and efficient adsorbents. This paper proposes a highly efficient Cr(VI) adsorbent based on tannic acid coating PVA/PVP/PEI nanofibrous membrane. The adsorbent is environment-friendly and has satisfying water stability and adsorption performance. The optimum preparation conditions, adsorption conditions, and the influence of ionic strength and coexisting ions were investigated comprehensively. Through the study of adsorption kinetics and isotherms, the adsorption of Cr(VI) on the nanofibrous membrane was found following the pseudo-second-order kinetics model, and the adsorption isotherm model following the Langmuir model. The maximum adsorption capacities were 631.97 mg/g, 667.52 mg/g, and 695.04 mg/g at 298 K, 308 K, and 318 K, respectively. After adsorption of Cr(VI), the membrane can be converted to high purity Cr 2 O 3 by calcination. The tannin-coated PVA/PVP/PEI nanofibrous membrane is a promising adsorbent because it can efficiently adsorb Cr(VI) and convert highly toxic Cr(VI) into hypotoxic Cr(III).
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
危险品化学品经营许可证（带存储）