SOLID STATE IONICS
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2020
·
IF 3.107
Ying Zhou,Tingting Zhou,Yipeng Zhang,Li Tang,Qing Guo,Mingfeng Wang,Changsheng Xie,Dawen Zeng
Core-shell heterostructures of metal oxide semiconductor (MOS) and metal organic framework (MOF) improve gas-sensing properties due to the MOF's molecular sieving effects. However, the selection of MOF is limited by the requirement of identical metal element in MOF to that in MOS, which is crucial for valid interface adhesion. In this paper, WO 3 @ZIF-71 (zeolitic imidazolate framework) structure with different metal elemental components (W and Zn) was fabricated by a step-by-step (SBS) approach. As a result, ZIF-71 was uniformly coated on the surface of WO 3 . In order to explore the influence of ZIF-71 (pore size: 4.8 Å), the gas sensitivity of WO 3 and WO 3 @ZIF-71 were tested. Different kinetic diameters gases: H 2 S (3.62 Å), CH 3 COCH 3 (4.6 Å), CH 3 CH 2 OH (4.53 Å), NO 2 (5.8 Å) were selected as testing gas. Gases with small molecules (H 2 S, CH 3 COCH 3 and CH 3 CH 2 OH) can pass through the membrane of ZIF-71 and contact with WO 3 , while larger ones (NO 2 ) were blocked outside the membrane. Excitingly, the response of WO 3 @ZIF-71 toward H 2 S gas was significantly improved, which soars from 2.24 of 20 ppm for pure WO 3 to 19.12 for H 2 S at 250 °C, increased about 9 times. These results indicate that the MOS@MOF core-shell structure can be synthesized by the SBS method without the restriction of the same metal elements in MOS and MOF, which is also an effective approach to regulate the selectivity and sensitivity of the MOS@MOF gas sensor.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
RSC Advances
·
2014
·Vol. 5
·期 10
·7253-7259
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IF 3.708
Yuanlong Xiao,Xiangyu Guo,Hongliang Huang,Qingyuan Yang,Aisheng Huang,Chongli Zhong
A cheap and biocompatible metal–organic framework MIL-88B(Fe) (MIL = Material Institut Lavoisier) was synthesized and incorporated into Matrimid® 5218 to fabricate mixed-matrix membranes (MMMs) for gas separation. Separation performances of the MIL-88B(Fe)/Matrimid MMMs were tested for the single gas permeation of H2 and CH4 as well as the mixture gas separation of an equimolar binary H2–CH4 mixture. Due to the molecular sieving effect, the incorporation of MIL-88B(Fe) can enhance H2 permeability but hinder the transport of CH4 in MIL-88B(Fe)/Matrimid MMMs, thus resulting in enhanced separation selectivity of H2–CH4. At 298 K and ΔP = 3.0 bar, compared with those of a pure polymeric membrane, the H2 permeability and H2–CH4 mixture separation factor of MMMs with a MIL-88B(Fe) loading of 10% increased by 16% and 66%, respectively. In addition, the operation temperature has a significantly positive effect on the separation of a H2–CH4 mixture.
研究领域:
材料科学
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气体分离工程
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DOI
高影响因子
KOREAN JOURNAL OF CHEMICAL ENGINEERING
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2023
·Vol. 40
·期 1
·195-204
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IF 2.7
Wu Hongdan,Liu Xiaodi,Yang Xiaoyu,Hu Chuanzhi,Zhou Zhihui
Organosilica membranes derived from bis(triethoxysilyl)ethane (BTESE) and tetraethyl orthosilicate (TEOS) were prepared by sol-gel method on porous α -Al 2 O 3 supports and applied in pervaporation dehydration of isopropanol (IPA) aqueous solutions. The permeation characteristics of membranes in IPA/water mixture were evaluated for preparation conditions and stability, including long-term stability, acid resistance, and feed concentration. It was observed that the water contact angle of BTESE/TEOS-derived organosilica membrane decreased from (77.74±0.47)° to (36.67±1.05)° as the content of TEOS increased, which proved that the surface property of the membrane could be changed by the part of hydrocarbon units after hydrolysis condensation reaction. As the molar ratio of BTESE to TEOS was 1 : 2, the organosilica membrane showed high pervaporation performance for 90 wt% isopropanol aqueous solutions at 75 °C, with a water permeation flux of 10.580 kg·m −2 ·h −1 and separation factor of 1170. Stability experiments of long-term operation and acid environment in isopropanol aqueous solutions showed slight changes in flux and separation factor, proving that organosilica membranes had better stability. An increase in IPA concentration from 60 wt% to 90 wt% decreased both water flux and water content on the permeate side, suggesting that the effective pore sizes for permeation could be reduced by adsorption of IPA molecules, whereas the membrane remained high permeance in isopropanol aqueous solutions with high water content. The separation mechanism of pervaporation dehydration of isopropanol aqueous solutions by BTESE/TEOS-derived membrane was mainly attributed to the molecular sieve separation effect. The results showed that the BTESE/TEOS-derived organosilica membranes had an application prospect in the dehydration of aqueous-organic mixtures.
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
CHEMICAL ENGINEERING JOURNAL
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2022
·
IF 16.744
Wan-Qi Sun,Jian-Bo Hu,Yun-Jia Jiang,Nuo Xu,Ling-Yao Wang,Jia-Hao Li,Yong-Qi Hu,Simon Duttwyler,Yuan-Bin Zhang
The separation of C 2 H 2 /CO 2 is an important process in industry but challenged by the trade-off of capacity and selectivity owning to their close physical properties and identical kinetic molecular size. Herein, we reported a new metal organic framework ZNU-3 (ZNU = Zhejiang Normal University) with flexibility controlled by abundant hydrogen-bonds for highly selective molecular sieving of C 2 H 2 from CO 2 , CH 4 , C 2 H 4 and C 2 H 6 using commercially available cost-effective ligands. At 1.0 bar and 298 K, the uptake capacity of C 2 H 2 is 81.0 cm 3 (STP) g −1 , while the CO 2 , C 2 H 4 , C 2 H 6 , CH 4 , N 2 uptake capacities are only 5.4, 5.3, 1.0, 1.1, 1.1 cm 3 (STP) g −1 , respectively. Such high uptake ratios of C 2 H 2 over other C2 and C1 gases have rarely been achieved. Particularly, the C 2 H 2 /CO 2 uptake ratio of 14.9 is only secondary to that of the benchmark UTSA-300a and much higher than those of all other porous materials. Dynamic breakthrough experiments with equimolar C 2 H 2 /CO 2 mixtures showed that the retaining time of C 2 H 2 is nearly 2 fold of that of CO 2 , indicating the excellent practical separation performance of ZNU-3 for C 2 H 2 /CO 2 mixtures. Modeling studies indicated that C 2 H 2 is mainly trapped by two opposite carboxylic groups with additional small contribution from π···π packing between pyridine ring and planar C≡C moiety.
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
ACS Sustainable Chemistry & Engineering
·
2015
·
IF 4.642
Lin-Bing Sun,Ying-Hu Kang,Yao-Qi Shi,Yao Jiang,Xiao-Qin Liu
Owing to their high physicochemical stability and low skeleton density, polymers are highly promising for capturing the greenhouse gas CO2. However, complicated monomers, expensive catalysts, and/or severe conditions are usually required for their synthesis, which makes the process costly, tedious, and hard to scale up. In this paper, a facile nucleophilic substitution reaction is developed to synthesize polymers from low-cost monomers, namely chloromethylbenzene and various diamines. Due to the appropriate reactivity of monomers, the polymerization takes place at a low temperature of about 60 °C in the absence of any catalysts. A series of polymers containing plentiful secondary amines are successfully fabricated; these secondary amines provide a proper adsorbate–adsorbent interaction from the viewpoints of selective capture of CO2 and energy-efficient regeneration of adsorbents. Moreover, the materials possess well-defined micropores with the dimension close to the size of adsorbate molecules and subsequently, exhibit the molecule sieving effect. As a result, these materials are active in selective adsorption of CO2 and show high CO2/N2 and CO2/CH4 selectivities. More importantly, the adsorbents can be completely regenerated under mild conditions, and no loss in activity is detected after eight cycles.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2023
·
IF 8.6
Ruimin Zhu,Lucy Wang,Huayu Zhang,Chunjie Liu,Zhengbao Wang
ZIF-8 membranes have attracted extensive research attention due to their ease of synthesis, stable properties, and wide applicability. Compared to expensive inorganic supports, organic polymer supports are more flexible and inexpensive. However, addressing the issue of weak adhesion between the surface of the organic support and the ZIF-8 membrane layer poses a significant challenge. In this study, we present a strategy for preparation of ZIF-8 membrane by the fabrication of an asymmetric dual-layer polymeric hollow fiber support using polyvinylidene fluoride (PVDF) as the material. The outer layer of the support is composed of PVDF embedded with ZIF-8 seeds, while the inner layer consists of pure PVDF. This approach addresses the weak adhesion between the support and the ZIF-8 membrane layer formed through a one-step solvothermal crystallization process. The effects of ZIF-8 seed size, content, and crystallization conditions on the membrane structure and performance are investigated. Under the synergistic molecular sieving effects of ZIF-8 continuous membrane layer and ZIF-8 crystals within the outer layer of the support, larger gas molecules are difficult to penetrate the membrane layer, making the resulting membrane highly selective for the gas separation. Under the optimal fabrication conditions, the H 2 permeability of the ZIF-8 membrane is determined to be 1.52 ± 0.1 × 10 −7 mol·Pa −1 ·s −1 ·m −2 , with a H 2 /N 2 ideal separation selectivity of 69.5 ± 4. This method demonstrates simplicity and high reproducibility for preparation of ZIF-8 membranes on dual-layer hollow fibers, and it is expected to be extended to the growth and fabrication of other MOF 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
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Qingping Xin,Sining Kong,Xueting Cao,Yucheng Pan,Kun Wan,Hao Chen,Huimin Jin,Ningning Gao,Xiaoli Ding,Yuzhong Zhang
At the present time, the realm of gas separation membranes is predominantly centered on the development of membrane materials that simultaneously exhibit exceptional gas permeability and selectivity. Mixed Matrix Membranes (MMMs) hold significant promise in addressing the long-standing challenge of balancing membrane selectivity with permeability. By incorporating a molecular sieving mechanism, an enhanced gas separation process is achieved. In this research endeavor, single-layer MXene nanosheets serve as an ideal substrate for the direct growth of ZIF-8 nanoparticles, yielding heterogeneously structured nanofillers, coined ZIF-8@MXene. The composite filler, ZIF-8@MXene, maintains a two-dimensional lamellar structure reminiscent of MXene, while also integrating ZIF-8 nanoparticles with their optimal pore size of 3.4 Å. This optimal pore size efficiently facilitates the unimpeded passage of CO 2 molecules through the channels, creating a preferential pathway. Conversely, N 2 molecules encounter greater difficulty traversing these channels, effectively coupling the solubility-diffusion mechanism with the molecular sieving mechanism to enhance selectivity in gas separation processes. Consequently, the mixed matrix membrane exhibits a remarkable enhancement in gas selectivity. Particularly, under sub-ambient conditions (−20 °C), the PEO/ [email protected] % membrane achieves an exceptional CO 2 /N 2 selectivity of 294.1, accompanied by a high CO 2 permeability of 115.58 Barrer. This outstanding performance surpasses the 2019 upper bound, underscoring the significant potential of heterostructured nanofillers to be harnessed in advancing various mixed matrix membranes (MMMs) towards high-performance gas separation capabilities.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2012
·
IF 4.531
Na Chang,Xiu-Ping Yan
Metal-organic frameworks (MOFs) which offer a variety of topologies, porous networks and high surface areas are promising and have potential for the applications of specific adsorption, isomerization, catalysis and separation. UIO-66 is the first MOF that has been observed to have reverse shape selectivity. However, such reverse shape selectivity of MOFs has never been explored for capillary gas chromatographic separation. Here we report the fabrication of MOF UIO-66 coated capillary column and exploration of the reverse shape selectivity and molecular sieving effect of such column for capillary gas chromatographic separation of alkane isomers and benzene homologues with excellent selectivity and precision. The adsorption enthalpies and entropies on the interaction between hydrocarbons and UIO-66 were measured to illustrate the energy effect on the separation of alkane isomers and benzene homologues on the UIO-66 coated capillary column. UIO-66 coated capillary column gave preferential retention of branched alkane isomers over their linear isomer, showing reverse shape selectivity, making UIO-66 coated capillary column attractive for capillary gas chromatographic separation of alkane isomers. iso -Propylbenzene (branched) eluted after n -propylbenzene on the UIO-66 coated capillary column again shows reverse shape selectivity. However, much bulkier 1,3,5-trimethylbenzene eluted earlier than n -propylbenzene and iso -propylbenzene on the UIO-66 coated capillary column, exhibiting molecular sieving effect. The combination of reverse shape selectivity with molecular sieving effect makes the UIO-66 coated capillary column promising for the separation of structural isomers.
研究领域:
化学
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材料科学
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产品关联
DOI
PubMed
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2023
·
IF 5.9
Yong Zhu,Hailun Li,Huiran Jin,Jingrui Ma,Zhandong Ye,Bingmin Wu,Ying Zhang,Qingping Xiong,Shijie Ding,Jing Chen,Song Huang
Alkaloids are the most medicinally valuable ingredients in plant crop Coptis chinensis ( C. chinensis ). However, the separation of these small-molecule compounds is challenging because C. chinensis also contains a lot of impurities such as proteins and saccharides . Adsorption separation stands out in the field of biological separation by virtue of its efficiency and greenness. Here, this paper aimed to selectively separate the total alkaloids during extraction of C. chinensis by resorcinol-formaldehyde (RF) aerogel based on electrostatic interaction and size-sieving effect. First, RF aerogels with different surface area (40.6–674.9 m 2 /g) and pore size (2–25 nm approximately) were synthesized by adjusting the ratio of catalyst (C). The results of static adsorption showed that the optimum alkaloids selective separation was achieved at R/C of 10/1: alkaloids adsorption capacity ( Q e ), protein retention ratio ( Pr ), saccharides retention ratio ( Sr ) and the coefficient of selectivity were 487.93 mg/g, 87.40 %, 95.90 % and 2.23, respectively. Methanol containing 1 % hydrochloric acid was considered as the most suitable eluent with the desorption efficiency of 95.88 %. In addition, the adsorption process conformed to pseudo-second-order kinetics, intra-particle diffusion and Langmuir isotherm models, and was a spontaneous endothermic process. It was found from the dynamic adsorption experiment that the dynamic adsorption capacity was 497.81 mg/g, and the purity of total alkaloids increased from 39.19 % to 90.22 %. Compared with resin adsorption and salt precipitation method, RF aerogel separation could more efficiently separate the alkaloids from C. chinensis (the total alkaloids yield of 57.40 mg/g C. chinensis ). In addition, the alkaloids separated by RF aerogel had better antioxidant and antibacterial activities than that separated by salt precipitation method. In summary, RF aerogel separation was potential as an efficient and green method for the separation of total alkaloids from C. chinensis .
研究领域:
植物化学
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药物分离工程
·
生物医学
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DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2025
·
IF 7.7
Longyu Ren,Yuhang Du,Ya Wang,Jinan Li,Ruojin Zhang,Jiliang Yuan,Hongyan Xu
In 2 O 3 , as a traditional metal oxide semiconductor substrate material, responds to various toxic and harmful gases but with poor selectivity. This paper uses the hydrothermal method to grow dense and uniform In 2 O 3 nanorods vertically on a ceramic tube, and then covers them with ZIF-71. By adjusting the type of solvent used to synthesize ZIF-71, the morphology and properties of the material can be changed. The pores and large specific surface area of ZIF-71 are utilized to sieve large molecular gases, providing more adsorption sites for NO 2 gas. And it forms heterostructure with In 2 O 3 to enhance the response to NO 2 . The optimized gas sensor In 2 O 3 @ZIF-71(CH 3 OH) shows superior response (185, S=R g / R a ) and selectivity of 50 ppm triethylamine as an interfering gas (7.23, S=R a / R g ) to 50 ppm NO 2 compared to pure In 2 O 3 nanorods. Molecular dynamics simulation is used to study the gas adsorption performance of ZIF-71 and theoretical simulation of the adsorption behavior of NO 2 on the In 2 O 3 substrate is conducted through density functional theory. The simulation results show that the ZIF-71 molecular sieve can reduce the response to large molecule TEA gas through the dual effects of pore size adsorption and blocking, thereby improving the selectivity of the material. Indium oxide (In 2 O 3 ) has an adsorption effect on nitrogen dioxide (NO 2 ), with an adsorption heat of 0.499 electron volts, and its adsorption effect is relatively stable.
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高影响因子
Journal of Materials Chemistry B
·
2015
·Vol. 3
·期 20
·4242-4248
·
IF 4.726
Xiangyang Zhu,Jinlou Gu,Jian Yang,Zhe Wang,Yongsheng Li,Liming Zhao,Wenru Zhao,Jianlin Shi
The accurate characterization of low abundance phosphopeptides based on mass spectrometry (MS) techniques remains a challenge due to signal suppression by the large excess of interfering proteins and non-phosphopeptides. This demands better methods to effectively enrich phosphopeptides prior to MS analysis. In the current work, facilely synthesized Zr-based metal–organic frameworks (MOFs) of UiO-66 and UiO-67 have been successfully exploited as novel affinity materials for the enrichment and analysis of phosphopeptides. Thanks to their abundantly existent and naturally exposed Zr–O clusters, intrinsically large surface areas and highly ordered open cavities, UiO-66 and UiO-67 exhibited sensitive and specific enrichment of phosphopeptides with an interesting molecular sieving effect. An optimized protocol for loading, washing and elution was developed. Under these most optimized conditions, specific accumulation was demonstrated by the selective enrichment of phosphopeptides in the presence of abundant non-phosphorylated species. Meanwhile, high-abundance interfering proteins could be effectively excluded during the enrichment process. Additionally, the MOFs have also been successfully used to enrich phosphopeptides from human serum. These merits combined with their high chemical and thermal stabilities, make UiO-66 and UiO-67 highly promising for applications in phosphopeptidome research.
研究领域:
生物化学
·
分析化学
·
蛋白质组学
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DOI
PubMed
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2021
·
IF 8.742
Fangmeng Sheng,Xingya Li,Yuanyuan Li,Noor Ul Afsar,Zhang Zhao,Liang Ge,Tongwen Xu
Wastewater containing organic dyes and high content of salts has posed a serious challenge on global water security. Herein, a cationic nanoporous covalent organic framework (COF) membrane is constructed via a facile interfacial growth strategy. The prepared membranes show excellent dye/salt separation performance with a pure water flux above 24 L m −2 h −1 bar −1 . The rejection rate of methylene blue of positive charges is above 99%, while the rejection rates of NaCl, Na 2 SO 4 , MgSO 4 are only 3.2%, 2.6%, and 9.4%, respectively. The high rejection of methylene blue is mainly governed by the electrostatic repulsion between cationic COF channels and the positively charged dye. Moreover, the size sieving effect dominates the rejection of dyes with larger molecular sizes than that of the COF channel. These findings provide strategies for developing various nanoporous COF membranes for efficient dye/salt separation.
研究领域:
材料科学
·
环境科学
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DOI
高影响因子
危险品化学品经营许可证（带存储）