Analytical Methods
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2020
·Vol. 12
·期 19
·2434-2442
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IF 2.596
Lian Wen,Peng Wu,Lei-Lei Wang,Li-Zong Chen,Ming-Lin Wang,Xia Wang,Jin-Ming Lin,Ru-Song Zhao
Covalent organic frameworks with tunable porous crystallinity and outstanding stability have recently exhibited fascinating pretreatment performance as solid-phase microextraction coatings. In this report, a β-ketoenamine-linked covalent organic framework (TpPa-1) was successfully constructed through a Schiff-base-type reaction between 1,3,5-triformylphloroglucinol (Tp) and para-phenylenediamine (Pa-1). A TpPa-1 coating was then fabricated on a stainless-steel fiber for capturing trace synthetic musks. This TpPa-1 coating exhibited strong interaction with synthetic musks because of its hydrophobicity and π–π affinity. This TpPa-1-based solid-phase microextraction methodology, coupled with gas chromatography-tandem mass spectrometry, provided high enrichment factors (1214–12 487), wide linearity (0.5–1000 ng L−1), low limits of detection (0.04–0.31 ng L−1), and acceptable reproducibility (relative standard deviation, <10%) for nine synthetic musks. Recoveries at three spiked levels in three types of water samples were between 76.2% and 118.7%. These results indicated the promising applicability of the TpPa-1 as a solid-phase microextraction fiber coating for reliably detecting trace concentrations of synthetic musks in the environment.
研究领域:
分析化学
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环境科学
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材料科学
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DOI
高影响因子
CHINESE JOURNAL OF POLYMER SCIENCE
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2022
·Vol. 40
·期 4
·338-344
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IF 3.815
Yang Guang-Hui,Zhang Zhe,Yin Cong-Cong,Shi Xian-Song,Wang Yong
Two-dimensional covalent organic frameworks (COFs) with specific morphologies including nanofibers and nanoplates are highly desired in both nanoscience research and practical applications. Thus far, however, morphology engineering for COFs remains challenging because the mechanism underlying the morphology formation and evolution of COFs is not well understood. Herein, we propose a strategy of surfactant mediation coupled with acid adjustment to engineer the morphology of a β -ketoenamine-linked COF, TpPa, during solvothermal synthesis. The surfactants function as stabilizers that can encapsulate monomers and prepolymers to create micelles, enabling the formation of fiber-like and plate-like morphologies of TpPa rather than irregularly shaped aggregates. It is also found that acetic acid is important in regulating such morphologies, as the amino groups inside the prepolymers can be precisely protonated by acid adjustment, leading to an inhibited ripening process for the creation of specific morphologies. Benefitting from the synergistic enhancement of surfactant mediation and acid adjustment, TpPa nanofibers with a diameter down to ∼20 nm along with a length of up to a few microns and TpPa nanoplates with a thickness of ∼18 nm are created. Our work sheds light on the mechanism underlying the morphology formation and evolution of TpPa, providing some guidance for exquisite control over the growth of COFs, which is of great significance for their practical applications.
研究领域:
材料科学
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纳米技术
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化学工程
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产品关联
DOI
高影响因子
Materials Today Energy
·
2022
·
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
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2024
·
IF 3.8
Yiran Xia,Lushuai Wang,Yang Liu,Jiawei Liu,Quan Bai
Covalent organic frameworks (COFs) show promise as a stationary phase in high performance liquid chromatography (HPLC). However, there are only a few COFs-based stationary phases developed for HPLC separation so far. Therefore, it is crucial to not only develop more varieties of COFs-type stationary phases for HPLC separation, but also to explore the retention mechanism of solutes on these stationary phases. In this paper, a new in-situ growth method was developed to prepare β -ketoenamine COF-TpPa-1@SiO 2 composite microspheres, using spherical silica as the core material and COF-TpPa-1 fabricated by covalent conjugation of 1,3,5-triformylphloroglucinol (Tp) and p -phenylenediamine (Pa-1) as the COF shells. The resulting microspheres exhibit uniform morphology, good monodispersity, large specific surface area, narrow size distribution, and high stability. Due to diverse functional groups in the structure of COF-TpPa-1, the microspheres can offer multiple interactions, such as hydrophobic, π-π stacking and electron-donor–acceptor (EDA) between COFs and analytes. As a result, the COF-TpPa-1@SiO 2 composite microspheres can be used as a mixed-mode stationary phase for HPLC separation. The chromatographic performance and retention mechanism of the COF-TpPa-1@SiO 2 packed column were investigated by separating polar and non-polar solutes, as well as isomers, in various HPLC modes, including reversed-phase liquid chromatography (RPLC), hydrophilic interaction chromatography (HILIC), and RPLC/HILIC mixed-mode chromatography. The results showed successful separation of non-polar alkylbenzene homologues, polycyclic aromatic hydrocarbons (PAHs), and polar amines and phenols in RPLC mode. The “U-shaped” curves of retention factor with the ACN concentration in mobile phase for four nucleobases indicated that the solute retention on the column followed a mixed mode mechanism of RPLC/HILIC. Compared to a traditional C18 column, the COF-TpPa-1@SiO 2 column exhibited superior separation efficiency, stability, repeatability and reproducibility in the separation of analytes with different polarities. The column enhanced the aromatic, shape and planar selectivity for PAHs and isomers through π-π interaction and improved the separation efficiency for electron-deficient compounds due to EDA effect. At last, the column was successfully used to separate and detect the residues of 5 phenylurea herbicides (PUHs) in soil. All these results indicate the potential of COFs for chromatography applications.
研究领域:
分析化学
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材料科学
·
色谱学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2021
·
IF 8.128
Wei Wang,Cong Liu,Mutian Zhang,Chenyang Zhang,Lin Cao,Chunfeng Zhang,Tengfei Liu,Debao Kong,Wen Li,Shougang Chen
It is a major challenge to combine the advantages of two kinds of two-dimensional materials to construct a heterojunction and achieve efficient photocatalytic antifouling. In this work, we covalently connected two materials MXenes and covalent organic frameworks (COFs) through the Schiff base reaction and anchored Ag nanoparticles (NPs) to prepare a Ti 3 C 2 /TpPa-1/Ag composite material with high efficiency bactericidal properties. The covalent bonding between MXene and COF greatly improved the stability of the material. Ti 3 C 2 /TpPa-1/Ag composite showed an excellent antibacterial property against S. aureus and P. aeruginosa . The fluorescence spectra of Ti 3 C 2 /TpPa-1/Ag proved that the electron transfer channels formed between the ternary materials could greatly improve the efficiency of carrier separation and prolong the life of photogenerated carriers. Density functional theory calculations showed that the synergistic catalytic effect of Ag and Ti 3 C 2 could greatly reduce the work function along the interface, and the built-in electric field between the layers drive carrier fast migration, which effectively improve the catalytic performance.
研究领域:
材料科学
·
纳米技术
·
光催化
·
抗菌材料
✓ 已验证
DOI
PubMed
高影响因子