Materials Today Chemistry
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2025
·
IF 6.7
Huaiyin Chen,Zhonghe Wang,Jun Li,Xiaolin Liu,Congxiang Li,Yongzhao Li,Weihe Yu,Longmin Liu,Yi Zhang,Yuekun Lai,Weilong Cai
ZIF-8 is considered as a promising functional material in anti-corrosion coating applications. However, ZIF-8 hydrolyzes easily, especially in acidic and salty media, due to its unstable Zn–N coordination bonding and hydrophilic crystal surface, which reduces anti-corrosion durability of the coatings. In this study, highly hydrophobic modification of ZIF-8 particles was performed through simple surface ligand exchange with 5,6-dimethylbenzimidazole (DMBIM). The as-prepared ZIF-8/DMBIM particles showed high water-repellency and enhanced chemical stability in acidic, neutral, and alkaline media, and excellent compatibility and barrier function in epoxy coatings. As a consequence, ZIF-8/DMBIM modified epoxy coatings showed significantly enhanced corrosion resistances in acid, alkali and salt aqueous solutions with pH 3.0–11.0. Electrochemical impedance spectroscopy tests demonstrated that, after 20 days of immersion in 3.5 wt% NaCl solution at all the studied pH, the |Z| 0.01 Hz values of ZIF-8/DMBIM modified epoxy coatings were approximately two orders of magnitude higher than of the original epoxy coatings. This work provides an idea for the development and application of ZIF materials in more fields, and innovative anti-corrosion coatings based on functional modification of materials.
研究领域:
材料科学
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腐蚀与防护
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DOI
高影响因子
International Journal of Electrochemical Science
·
2023
·
IF 1.5
Huimin Yang,Xin Liu,Jihui Wang,Wenbin Hu
The following study is conducted to improve the corrosion resistance of magnesium alloy. First, ZnAl layered double hydroxide (ZnAl LDH) film was prepared on AZ61 magnesium alloy by using hydrothermal method. Then, as-prepared ZnAl LDH was put into 2-methylimidazole (2-mIm) solution to synthetize ZIF-8 film (ZIF-8/LDH). Finally, ZIF-8/LDH film synthesized ZIF-8-DMBIM film (ZIF-8-DMBIM/LDHs) via a shell-ligand-exchange-reaction in the methanol solution containing 5, 6-dimethylbenzimidazole (DMBIM). The surface morphology, structure, and composition of the composite film were observed and determined by scanning electronic microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and energy-dispersive X-ray spectroscopy. The wettability of composite film was measured by using a water contact angle meter, and the corrosion resistance of the composite film was estimated by the polarization curve and electrochemical impedance spectroscopy techniques. Results show that the prepared ZIF-8-DMBIM/LDH composite film has a dense hexagonal plate morphology with a two-layer structure and a thickness of 3.5 μm. Compared with ZnAl LDH and ZIF-8/LDH films, ZIF-8-DMBIM/LDH composite film has a high contact angle (115.7°), low corrosion current density, and high corrosion potential and polarization resistance due to its near-smooth surface, dense two-layer structure, and hydrophobic characters.
研究领域:
材料科学
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电化学
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DOI
高影响因子
MOLECULES
·
2024
·Vol. 29
·期 18
·4465
·
IF 4.2
Yun Xiong,Yifan Shu,Niyan Deng,Xiaogang Luo,Shengpeng Liu,Xiaoyu Wu
This study investigated the enhancement in bioethanol recovery from mixed matrix membranes (MMMs) by functionalizing zeolite framework-8 (ZIF-8) with imidazolate. This study focused on the separation of ethanol from low-concentration ethanol/water mixtures (typical post-fermentation concentrations of 5–10 wt%). Specifically, ZIF-8 was modified by the shell–ligand exchange reaction (SLER) with 5,6-dimethylbenzimidazole (DMBIM), resulting in ZIF-8-DMBIM particles with improved hydrophobicity, organophilicity, larger size, and adjustable pore size. These particles were incorporated into a PEBAX 2533 matrix to produce ZIF-8-DMBIM/PEBAX MMMs using a dilution blending method. The resulting membranes showed significant performance enhancement: 8 wt% ZIF-8-DMBIM loading achieved a total flux of 308 g/m2·h and a separation factor of 16.03, which was a 36.8% increase in flux and 176.4% increase in separation factor compared with the original PEBAX membrane. In addition, performance remained stable during a 130 h cycling test. These improvements are attributed to the enhanced compatibility and dispersion of ZIF-8-DMBIM in the PEBAX matrix. In conclusion, the evaluation of nanofiller content, feed concentration, operating temperature, and membrane stability confirmed that ZIF-8-DMBIM/PEBAX MMM is ideal for ethanol recovery in primary bioethanol concentration processes.
研究领域:
材料科学
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化学工程
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DOI
PubMed
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2024
·
IF 8.4
Ning Li,Chao Ma,Ziyue Wang,Dudu Li,Zhihua Qiao,Chongli Zhong
The MOF crystal-glass composites (CGC) membrane, comprising a MOF crystal and MOF glass matrix, represents a novel self-supported membrane that has been effectively applied in gas separation. Nevertheless, the typical MOF glass matrix requires a higher operating temperature (>400 °C), which constrains its combination with a multitude of MOF crystals characterized by high porosity and low decomposition. In this work, Zn-P-dmbIm (coordination polymer) was chosen as the glass matrix, and MIL-101 crystal with high porosity were integrated at an operating temperature of 190 °C. Furthermore, the intrinsic low porosity of a g Zn-P-dmbIm can be enhanced by the incorporation of higher porosity MIL-101, which possessed a high specific surface area (from ∼1.7 m 2 /g to 401 m 2 /g) and porosity (from ∼0.0014 cm³/g/nm to 0.5605 cm³/g/nm) of the CGC. The intimate combination of MIL-101 and a g Zn-P-dmbIm by in - situ melting to reduce the interfacial defects, which also provides a robust foundation for effective CO 2 /N 2 separation. In CO₂/N₂ (50/50, v/v) mixed gas conditions, the MIL-101/ a g Zn-P-dmbIm membrane demonstrated a impressively high CO₂ permeability of 18670 barrer and CO₂/N₂ selectivity of 61, exceeding the CO₂/N₂ upper bound. The variable pressure (1-12 bar) and long-term stability (120 h) of the CGC membrane exhibited enhancing separation stability. Hence, the self-supported MIL-101/ a g Zn-P-dmbIm membrane demonstrated effective CO₂/N₂ separation performance, which had the potential to significantly extend the scope of applications for MOF crystal-glass matrices.
研究领域:
材料科学
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环境工程
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DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2025
·
IF 9
Zhihao Song,Xinrui Liu,De Ao,Zhihua Qiao,Zhi Wang,Song Zhao
Metal-organic framework glass shows great promise in gas separation applications, however, its inherent low porosity poses significant challenges to achieve the enhanced membrane permeability. In this work, we developed novel self-standing crystal-glass composite membrane via melt quenching process of porous organic cages and coordination polymer glasses. The resulting (CC3) n /( a g Zn-P-dmbIm) 1-n membranes effectively combines the high porosity of CC3 with the excellent film-forming property of Zn–P-dmbIm glass, enabling efficient CO 2 /CH 4 separation. Specifically, CO 2 molecules are preferentially adsorbed into the CC3 channels, followed by rapid permeation through the membrane, while the size exclusion restricts CH 4 molecules transport through the membranes. The obtained (CC3) 0.05 /( a g Zn-P-dmbIm) 0.95 membrane achieves a high CO 2 permeability of 9358 Barrer, a CO 2 /CH 4 selectivity of 24.2, and demonstrates 24-h operational stability. This study not only broadens the application scope of coordination polymer glasses in gas separation membranes but also provides novel insights for the design of high-performance crystal-glass composite membranes.
研究领域:
材料科学
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膜技术
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气体分离
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可持续能源
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聚合物化学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）