EUROPEAN POLYMER JOURNAL
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2019
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IF 3.621
Lixiao Chen,Jie Gao,Qi Wu,Hui Li,Shuqing Dong,Xiaofeng Shi,Liang Zhao
A novel multimode COF-300@SiO 2 chromatographic stationary phase was successfully prepared via an in situ growth strategy. Powder X-ray diffraction, solid nuclear magnetic resonance and scanning electron microscope confirmed the successful preparation of COF-300@SiO 2 chromatographic stationary phase. Multimode chromatographic performance and multiple retention mechanisms were investigated. Neutral and polar compounds were efficiently separated in reverse phase chromatography mode due to hydrophobic interaction, π-π interaction, electron-donor-acceptor interaction and size selectivity of porous structure, and the column exhibited comparable hydrophobic selectivity with C18 column. Especially, the size selectivity of porous structure promoted the separation of multicomponent compounds on the novel column. Only neutral compounds were completely or partly separated in normal phase chromatography mode based on π-π interaction, and the column showed better separation performance than SiO 2 column. Moreover, the column also presented weaker hydrophilic interaction than NH 2 /SiO 2 column in hydrophilic phase chromatography mode. Nucleosides, nucleobases and alkaloids were partly or completely separated on the developed column because of the presence of amino groups on the surface of COF-300. This work indicates promising application values of COFs-based chromatographic stationary phases in chromatographic separation areas.
研究领域:
分析化学
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材料科学
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产品关联
DOI
高影响因子
Surfaces and Interfaces
·
2025
·
IF 6.3
Yue Zhao,Da-Peng Wang,Guang-Long Zhang,Jin-Wei Zhang,Ji-Yong Zheng,Cun-Guo Lin
In this work, the carbon-based 2D-3D composite nanocontainers endowing coatings with both active and passive protection properties were constructed by the sp 2 /sp 3 hybridized carbon as a versatile strategy. The classic graphene oxide (GO, sp 2 C) and Covalent Organic Framework-300 (COF-300, sp 3 C) were chosen as examples and benzotriazole (BTA) as the inhibitor to fabricate the GO/COF-300@BTA nanocontainer. The composite nanocontainers embedded in polyvinyl butyral (PVB) coatings were applied on cupper substrates to get mechanical enhancement, active and passive corrosion protection performance. The tensile strength of GO/COF-300/PVB (12.38 Mpa) was two times higher than that pure PVB (5.96 MPa). The active protection performance was ensured by the corrosion inhibitors encapsulated in the 3D porous carbon skeleton. The passive protection performance was endowed by the maze effect of the 2D carbon-based nanosheets. The |Z| 0.01 Hz of Cu/(GO/COF-300@BTA)/PVB was higher than 10 9 Ω·cm 2 , which was two magnitudes larger than that of PVB coating, demonstrating the anti-corrosion properties. In addition, the quantum chemical calculation and molecular dynamics simulation results elaborated the adsorption states of BTA on copper substrate and the compatibility between the molecular chains of the PVB and the GO/COF-300 nanocontainer.
研究领域:
材料科学
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腐蚀与防护
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表面工程
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DOI
高影响因子
ACS Applied Materials & Interfaces
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2020
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IF 8.758
Peng Jin,Xiaoying Niu,Fang Zhang,Kui Dong,Hongxia Dai,Huige Zhang,Weifeng Wang,Hongli Chen,Xingguo Chen
Covalent organic frameworks (COFs), as one of the most significant members of the porous organic frameworks, have been well used in the photocatalysis owing to their outspread π-conjugated framework, high crystallinity and regular pore structure. Herein, after reducing the labile imine-linked COF-300 to the more stable amine-linked COF-300-AR, we for the first time demonstrated that COF-300-AR was the light-responsive oxidase mimic. COF-300-AR exhibited excellent oxidase-mimicking activity under purple light stimulation (λ = 400 nm), which can catalyze the oxidation of classical substrates such as 3,3′,5,5′-tetramethylbenzydine (TMB) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) by the formation of •OH and O2•– free radicals in the presence of dissolved oxygen. The COF-300-AR oxidase mimic has outstanding advantages of easy light control, high stability, good reusability, and highly catalytic oxidation capacity and has been applied to detect glutathione (GSH) levels in HL60 cells with good selectivity and high sensitivity. This study will broaden the sensing applications of COFs and offer a promising build block for the construction of artificial enzymes.
研究领域:
材料科学
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纳米技术
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分析化学
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生物化学
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DOI
PubMed
高影响因子
Nature Communications
·
2023
·Vol. 14
·期 1
·1-8
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IF 16.6
Chi Hongbin,Liu Yang,Li Ziyi,Chen Wanxin,He Yi
Flexible covalent organic frameworks (COFs) have been studied for applications containing sorption, selective separation, and catalysis. How to correlate the microscopic structure with flexibility in COFs is a great challenge. Herein, we visually track the flexible deformation behaviors of single COF-300 and COF-300-AR particles in response to solvent vapour guests with dark-field microscopy (DFM) in an in operando manner. COF-300-AR with freely-rotating C-N single bonds are synthesized by the reduction of imine-based COF-300 consisting of rigid C=N double bonds without changing topological structure and crystallinity. Unexpectedly, we observe that the flexible deformation of COF-300 is extremely higher than that of COF-300-AR despite it bears many C-N single bonds, clearly illustrating the apparent flexibility decrease of COF-300 after reduction. The high spatiotemporal resolution of DFM enables the finding of inter-particle variations of the flexibility among COF-300 crystals. Experimental characterizations by variable-temperature X-ray diffraction and infrared spectroscopy as well as theoretical calculations demonstrate that the flexible deformation of COF-300 is ascribed to the pedal motion around rigid C=N double bonds. These observations provide new insights into COF flexibility.
研究领域:
材料科学
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化学
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纳米技术
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产品关联
DOI
PubMed
高影响因子
Nature Communications
·
2025
·Vol. 16
·期 1
·1-9
·
IF 15.7
Wu Jinxiang,Wang Qianxi,Li Yanhao,He Yi
Three-dimensional covalent organic frameworks are promising multifunctional materials for applications in adsorption, separation, and catalysis. However, despite the continuous synthesis of an increasing number of three-dimensional covalent organic frameworks, little is known about the crystal growth pathways. Here, we report the real-time visual observation of the crystal growth process of COF-300 and LZU-79, two typical three-dimensional covalent organic frameworks, using in situ dark-field optical microscopy. Our dark-field optical microscopy imaging results reveal that two crystal-growth pathways are simultaneously operative during the liquid growth of COF-300 and LZU-79 microcrystals, including classical crystal growth modes and non-classical oriented attachment mechanisms. Specifically, detailed tracking of the trajectories between two rod-shaped single-crystal COF-300 pairs suggests that the oriented attachment process undergoes several distinct stages such as approach, alignment at (021) facets, tip-to-tip attachment, fusion, and shaping. Theoretical simulation results show that (021) facets of COF-300 microcrystals, which have a lower repulsive energy barrier due to steric solvation forces from intervening solvents, are energetically more favorable than (010) facets, inducing the oriented attachment between adjacent facets. This work enables a fundamental understanding of how three-dimensional covalent organic framework microcrystals grow dynamically, which can aid the further design of three-dimensional covalent organic frameworks with enhanced performances.
研究领域:
材料科学
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化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
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