JOURNAL OF MEMBRANE SCIENCE
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2024
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IF 8.4
Siqi Wu,Jianhua Qiu,Jiakai Wang,Li Wang,Chuyang Y. Tang
Covalent organic frameworks (COFs) with excellent solvent stability, high porosity, and well-designed pore size, are competitive candidates for organic solvent nanofiltration (OSN). To manipulate their structures, pre-synthetic and post-synthetic modifications are commonly used. Nevertheless, pre-synthetic modifications may alter the stacking fashion of COF nanosheets ; post-synthetic modifications are constrained by limited pre-functionalities and can hardly achieve complete conversion. In contrast, defect engineering is a facile method to modify the structure of COFs through defects generated by the breakage of linkages or the usage of end-capping molecules. In this study, we adopted defect engineering to improve the OSN performance of TpPa-COF membranes constructed of 2,4,6-triformylphloroglucinol (Tp) and p -phenylenediamine (Pa) monomers with end-capping molecules—aniline (An). The membrane synthesized with 30 percent of An molecules (TpPaAn-30/HPAN membrane) maintained a continuous COF layer with a thickness of ∼20 nm but lower density or more free channels, compared to the control membrane. The optimized TpPaAn-30/HPAN membrane had improved permeance for various organic solvents (e.g., 31.8 L m −2 h −1 bar −1 for methanol, fourfold of the control membrane) but maintained rejection towards methyl blue (>90 %). It also allowed the passage of rhodamine B but blocked methyl blue when filtrating a mixed-dye methanolic solution. Herein, the usage of end-capping monomers is proven to be an efficient method to introduce transport channels and improve the separation performance of COF membranes.
研究领域:
材料科学
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化学工程
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高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2024
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IF 8.4
Chenglin Zhang,Guangzhe Wang,Yangbo Qiu,Chao Wang,Feng Li,Long-Fei Ren,Jiahui Shao,Yiliang He
Covalent organic framework (COF) has great advantages in the field of membrane separation, but the efficient and convenient preparation of COF membranes is still a challenge. Herein, we propose a novel method with green solvent for the preparation of COF membranes based on electrostatic spraying, which can be successfully prepared within 10 min, forming the TpPa COF with a pore size of 1.8 nm. Molecular dynamics simulations demonstrate that electrostatic spraying enhances the reaction rate by lowering the energy barrier and increasing the movement of reacting monomers. Atomization of the solvent in electrostatic spraying causes the rapid volatilization of the solvent, resulting in supersaturation of the generated TpPa, precipitation and crystallization, and promotes the formation of TpPa COF structure. The optimal COF membrane for the separation of Congo red wastewater is prepared by adjusting the voltage, concentration, and spraying time, with selectivity of Na 2 SO 4 for Congo Red attaining 118 and water permeance reaching 70.2 L m -2 h -1 bar -1 . This work not only elaborates the membrane preparation mechanism in the electrostatic spraying process, but also greatly shortens the time of COF membrane preparation compared to the traditional method (2–3 days), which contributes to the possibility for practical application of COF membranes.
研究领域:
材料科学
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环境科学
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化学工程
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高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2026
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IF 9
Houyi Peng,Wenqi Zhang,Ji Chen,Qi Zhang,Xiao Xiao,Weixing Li
Polyamide nanofiltration membranes often exhibit reduced rejection rates and flux decline under high ionic strength conditions. In order to efficiently remove heavy metal ions (HMIs) from water, a TpPa-COF interlayered positive nanofiltration membrane was proposed. TpPa-1 COF was synthesized and then reacted with 1,3,5-Benzenetricarbonyl trichloride (TMC) to narrow the pore size. The narrowed pore size from 18 Å to 5.4 Å was designed for rejection of heavy metal ions (>5.8 Å). Then, the membrane was functionalized with polyethyleneimine (PEI) grafting to impart positive surface charges for enhanced HMIs removal. The developed membrane was systematically characterized and evaluated for its physicochemical properties and performance through attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), cold-field emission scanning electron microscope (SEM), and atomic force microscopy (AFM). The fabricated membrane achieved exceptional rejections of Cr 3+ (99.04 %), Mn 2+ (97.03 %), Co 2+ (97.74 %), Ni 2+ (98.43 %), Zn 2+ (98.85 %), and Cd 2+ (99.07 %) at a feed concentration of 1000 ppm. Notably, the membrane maintained the rejection efficiency of 90 % under a higher feed concentration of 6000 ppm, which is better than the commercial NF3 membrane. After 7 days of continuous operation, the rejection of HMIs exceeded 98.4 %, demonstrating the great stability. When treating actual electroplating wastewater, the membrane showed good performance. The removal rate for major ions (Cr(VI), Co 2+ , Cu 2+ , Mn 2+ , Ni 2+ , Zn 2+ ) reached from 97.4 % to 99.99 %. The developed membrane exhibited better performance than commercial membrane, demonstrating the practical potential in treating actual wastewater.
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高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2026
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IF 9.1
Rongpeng Yu,Qinya Huang,Wanyi Wang,Liangyin Xiang,Shakeel Zeb,Zhanchao Liu,Zheng Chuanbo,Yan Liu
This study explores the synthesis and application of a 2D block -shaped covalent organic framework(COF) and its integration into a surface molecularly imprinted polymers(SMIPs) for the selective adsorption of Myricetin(Myr) from food samples. The COF was synthesized using a binary deep eutectic solvent(DES1) composed of choline chloride and glycerol, while the molecularly imprinted polymers(MIPs) were polymerized on the surface of the COF utilizing a ternary deep eutectic solvent(DES2), consisting of choline chloride, acrylamide, and ethylene glycol. After optimizing the proportion of DESs, the resulting 50%-DES applied to COF(DC)-MIP exhibited a high adsorption capacity of 40.04 mg/g within 0.5 h at pH 6.0. The adsorption process, characterized by Langmuir isotherms and pseudo-second-order kinetics, was exothermic. The XPS and UV–Vis spectra confirm the adsorption mechanisms, indicating that Myr adsorption onto the COF-based MIP was predominantly driven by hydrogen bonding and π-π stacking interactions. Due to the COF serving as the matrix material, which enhances the structural stability and solvent resistance of the polymer, the 50%-DC-MIP demonstrated excellent recyclability, maintaining consistent performance over five cycles. Because of excellent selectivity, the 50%-DC-MIP was effectively employed to grape juice, bayberry juice and green tea resulting in satisfactory recoveries of 94.67% to 102.25%, 93.75% to 108.33% and 97.33% to 101.15%, respectively. These findings highlight the potential of COF-based MIPs for the selective extraction and detection of bioactive compounds like Myricetin in complex food samples, aligning with green chemistry principles by utilizing DES as environmentally friendly solvents.
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高影响因子
Materials Today Energy
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2022
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IF 9.257
Meng Xia,Ying Liang,Wenqi Luo,Dong Cai,Peng Zhao,Fanfan Chen,Yongpeng Li,Zhuyin Sui,Linlin Shan,Ruimei Fan,Fusheng Pan,Dong Wang,Meng Li,Yijun Shen,Juanxiu Xiao,Xilong Wu,Qi Chen
2D covalent organic frameworks (COFs) are a promising candidate in the field of solar-driven steam generation (SSG), though their applications are limited by the narrow-band spectral response, complicated framework design, expensive building blocks, and weak chemical stability in current stage. Herein, a composite photothermal material TpPa-COF@MoS 2 (MoCOF) with a core-shell structure is prepared by encapsulation of the MoS 2 micron-flowers with TpPa-COF via in situ growth to relieve the aforementioned shortcomings. Interestingly, the as-synthesized MoCOF not only presents an enhanced photothermal performance (78.5 °C, at 1 sun intensity) but also has a relative lower cost. Afterwards, a MoCOF@Gel SSG evaporator is fabricated by introducing MoCOF composites into the PVA (polyvinyl alcohol) polymer network . Attributing to the synergistic effects of efficient heat localization, hierarchical water pathways, and hydrophilic channels with a large specific surface area, the MoCOF@Gel shows a high evaporation rate up to 2.31 kg/m 2 /h and energy efficiency of 91.8% under one sun irradiation, which is superior to most of reported COF based steam generators. Furthermore, the MoCOF@Gel also shows robust mechanical property, satisfactory purification performance, and exceptionally antibacterial activity.
研究领域:
材料科学
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纳米技术
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太阳能
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环境科学
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高影响因子
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