共查询到20条相似文献,搜索用时 15 毫秒
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Danbo Wang Prof. Dr. Yingjie Zhao 《Angewandte Chemie (International ed. in English)》2023,62(13):e202302405
A weak CH/O hydrogen-bonded organic framework (HOF) with both rigidity and flexibility that could easily and reversibly switch from a non-crystalline to a crystalline phase was constructed. The specific solvent molecule acts as a “key” to control the crystallinity, while the highly rigid triangle macrocycle as the building block is the “lock”. The introduction and removal of the “key” could influence the local flexibility of the whole framework and lead to switchable crystallinity. Furthermore, the obtained HOF exhibits excellent separation efficiency for benzene and cyclohexane (94.4 %). 相似文献
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Mengchu Feng Ziru Niu Chunyan Xing Yehao Jin Prof. Dr. Xiao Feng Dr. Yuanyuan Zhang Prof. Dr. Bo Wang 《Angewandte Chemie (International ed. in English)》2023,62(33):e202306621
The design of porous microcapsules with selective mass transfer and mechanical robustness for enzyme encapsulation is highly desired for biocatalysis, yet the construction remains challenging. Herein, we report the facile fabrication of porous microcapsules by assembling covalent organic framework (COF) spheres at the interfaces of emulsion droplets followed by interparticle crosslinking. The COF microcapsules could offer an enclosed aqueous environment for enzymes, with size-selective porous shells that allow for the fast diffusion of substrates and products while excluding larger molecules such as protease. Crosslinking of COF spheres not only enhances the structural stability of capsules but also imparts enrichment effects. The enzymes encased in the COF microcapsules show enhanced activity and durability in organic media as verified in both batch reaction and continuous-flow reaction. The COF microcapsules offer a promising platform for the encapsulation of biomacromolecules. 相似文献
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Ze-Jiu Diao Si-Yi Liu Hui Wen Dr. Guoliang Liu Tao Yang Jing-Jing Li Prof. Xiao-Qin Liu Prof. Lin-Bing Sun 《Angewandte Chemie (International ed. in English)》2023,62(21):e202301739
Stimuli-responsive porous materials have captured much attention due to the on-demand tunable properties. Most reported stimuli-responsive porous materials are based on molecule isomerism or host-guest interaction, and it is highly desired to develop new types based on different responsive mechanism. Herein, inspired by natural cells which have the ability to fuse and divide induced by external stimulation, we report a new type of stimuli-responsive porous material based on detachment mechanism. A detachable porous organic polymer, namely DT-POP-1, is fabricated from the polymerization of anthracene-containing monomer (AnMon) when irradiated by 365 nm UV light. DT-POP-1 can detach into the monomer AnMon when irradiated with 275 nm UV light or heat. Such polymerization/detachment is reversible. The detachment results in a big difference in porosity and adsorption capacity, making the present detachable porous polymer highly promising in adsorptive separation and drug delivery. 相似文献
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Caitlin E. Shields Dr. Xue Wang Dr. Thomas Fellowes Rob Clowes Dr. Linjiang Chen Prof. Graeme M. Day Prof. Anna G. Slater Dr. John W. Ward Dr. Marc A. Little Prof. Andrew I. Cooper 《Angewandte Chemie (International ed. in English)》2023,62(34):e202303167
Hydrogen-bonded organic frameworks (HOFs) with low densities and high porosities are rare and challenging to design because most molecules have a strong energetic preference for close packing. Crystal structure prediction (CSP) can rank the crystal packings available to an organic molecule based on their relative lattice energies. This has become a powerful tool for the a priori design of porous molecular crystals. Previously, we combined CSP with structure-property predictions to generate energy-structure-function (ESF) maps for a series of triptycene-based molecules with quinoxaline groups. From these ESF maps, triptycene trisquinoxalinedione (TH5) was predicted to form a previously unknown low-energy HOF (TH5-A) with a remarkably low density of 0.374 g cm−3 and three-dimensional (3D) pores. Here, we demonstrate the reliability of those ESF maps by discovering this TH5-A polymorph experimentally. This material has a high accessible surface area of 3,284 m2 g−1, as measured by nitrogen adsorption, making it one of the most porous HOFs reported to date. 相似文献
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Zhenjie Mu Yuhao Zhu Yufeng Zhang Anwang Dong Chunyan Xing Ziru Niu Prof. Dr. Bo Wang Prof. Dr. Xiao Feng 《Angewandte Chemie (International ed. in English)》2023,62(17):e202300373
Pore environment and aggregated structure play a vital role in determining the properties of porous materials, especially regarding the mass transfer. Reticular chemistry imparts covalent organic frameworks (COFs) with well-aligned micro/mesopores, yet constructing hierarchical architectures remains a great challenge. Herein, we reported a COF-to-COF transformation methodology to prepare microtubular COFs. In this process, the C3-symmetric guanidine units decomposed into C2-symmetric hydrazine units, leading to the crystal transformation of COFs. Moreover, the aggregated structure and conversion degree varied with the reaction time, where the hollow tubular aggregates composed of mixed COF crystals could be obtained. Such hierarchical architecture leads to enhanced mass transfer properties, as proved by the adsorption measurement and chemical catalytic reactions. This self-template strategy was successfully applied to another four COFs with different building units. 相似文献
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Xiang Yu Gao Yao Wang Enyu Wu Chen Wang Bin Li Prof. Dr. Yaming Zhou Banglin Chen Dr. Peng Li 《Angewandte Chemie (International ed. in English)》2023,62(46):e202312393
Precise synthesis of topologically predictable and discrete molecular crystals with permanent porosities remains a long-term challenge. Here, we report the first successful synthesis of a series of 11 isoreticular multivariate hydrogen-bonded organic frameworks (MTV-HOFs) from pyrene-based derivatives bearing −H, −CH3, −NH2 and −F groups achieved by a shape-fitted, π–π stacking self-assembly strategy. These MTV-HOFs are single-crystalline materials composed of tecton, as verified by single-crystal diffraction, nuclear magnetic resonance (NMR) spectra, Raman spectra, water sorption isotherms and density functional theory (DFT) calculations. These MTV-HOFs exhibit tunable hydrophobicity with water uptake starting from 50 to 80 % relative humidity, by adjusting the combinations and ratios of functional groups. As a proof of application, the resulting MTV-HOFs were shown to be capable of capturing a mustard gas simulant, 2-chloroethyl ethyl sulfide (CEES) from moisture. The location of different functional groups within the pores of the MTV-HOFs leads to a synergistic effect, which resulted in a superior CEES/H2O selectivity (up to 94 %) compared to that of the HOFs with only pure component and enhanced breakthrough performance (up to 4000 min/g) when compared to benchmark MOF materials. This work is an important advance in the synthesis of MTV-HOFs, and provides a platform for the development of porous molecular materials for numerous applications. 相似文献
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Dr. Jikuan Qiu Chang Xu Xianhui Xu Yingjie Zhao Prof. Dr. Yang Zhao Dr. Yuling Zhao Prof. Dr. Jianji Wang 《Angewandte Chemie (International ed. in English)》2023,62(17):e202300459
Utilizing weak interactions to effectively recover and separate precious metals in solution is of great importance but the practice remains a challenge. Herein, we report a novel strategy to achieve precise recognition and separation of gold by regulating the hydrogen-bond (H-bond) nanotrap within the pore of covalent organic frameworks (COFs). It is found that both COF-HNU25 and COF-HNU26 can efficiently capture AuIII with fast kinetics, high selectivity, and uptake capacity. In particular, the COF-HNU25 with the high density of H-bond nanotraps exhibits an excellent gold uptake capacity of 1725 mg g−1, which is significantly higher than that (219 mg g−1) of its isostructural COF (COF-42) without H-bond nanostrap in the pores. Importantly, the uptake capacity is strongly correlated to the number of H-bonds between phenolic OH in the COF and [AuCl4]− in water, and multiple H-bond interactions are the key driving force for the excellent gold recovery and reusability of the adsorbent. 相似文献
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Yan Cheng Yan-Xiang Li Prof. Chun-Hua Liu Prof. Yuan-Yuan Zhu Prof. Wenbin Lin 《Angewandte Chemie (International ed. in English)》2023,62(41):e202310470
Porous organic polymers (POPs) have emerged as a novel class of porous materials that are synthesized by the polymerization of various organic monomers with different geometries and topologies. The molecular tunability of organic building blocks allows the incorporation of functional units for photocatalytic organic transformations. Here, we report the synthesis of two POP-based photocatalysts via homopolymerization of vinyl-functionalized diaryl dihydrophenazine (DADHP) monomer ( POP1 ) and copolymerization of vinyl-functionalized DADHP and 2,2′-bipyridine monomers ( POP2 ). The fluorescence lifetimes of DADHP units in the POPs significantly increased, resulting in enhanced photocatalytic performances over homogeneous controls. POP1 is highly effective in catalysing visible-light-driven C−N bond forming cross-coupling reactions. Upon coordination with Ni2+ ions, POP2-Ni shows strong synergy between photocatalytic and Ni catalytic cycles due to the confinement effect within the POP framework, leading to high efficiency in energy, electron, and organic radical transfer. POP2-Ni displays excellent activity in catalysing C−P bond forming reactions between diarylphosphine oxides and aryl iodides. They increased the photocatalytic activities by more than 30-fold in C−N and C−P cross-coupling reactions. These POP catalysts were readily recovered via centrifugal separation and reused in six catalytic cycles without loss of activities. Thus, photosensitizer-based POPs provide a promising platform for heterogeneous photocatalytic organic transformations. 相似文献
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Yanpei Song Dr. Joshua Phipps Changjia Zhu Prof. Dr. Shengqian Ma 《Angewandte Chemie (International ed. in English)》2023,62(11):e202216724
Water pollution is a growing threat to humanity due to the pervasiveness of contaminants in water bodies. Significant efforts have been made to separate these hazardous components to purify polluted water through various methods. However, conventional remediation methods suffer from limitations such as low uptake capacity or selectivity, and current water quality standards cannot be met. Recently, advanced porous materials (APMs) have shown promise in improved segregation of contaminants compared to traditional porous materials in uptake capacity and selectivity. These materials feature merits of high surface area and versatile functionality, rendering them ideal platforms for the design of novel adsorbents. This Review summarizes the development and employment of APMs in a variety of water treatments accompanied by assessments of task-specific adsorption performance. Finally, we discuss our perspectives on future opportunities for APMs in water purification. 相似文献
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JIA Yin FENG Fanda SONG Xinyu SHI Zhiqiang SUN Lin JIANG Ruiyu TANG Lanqin ZHANG Lei 《高等学校化学研究》2023,39(2):310-317
The adsorption method is considered to be one of the most promising organic pollutants emission reduction strategies. The design and synthesis of high-performance porous adsorbents are one of the most important but challenging works. In this work, we constructed a new class of porous molecular cage switches by a simple reaction using phenolphthalein as the raw material. The molecular cage switches displayed interesting on-off behavior towards organic guests, which is highly responding to organic pollutants with rapid color change and is also able to adsorb these organic pollutants through an open-to-close pathway. This molecular cage switch also has excellent regenerative cycling properties and water resistance, which is expected to be employed in the handling of organic pollutants in the future. 相似文献
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Dr. Yong Lu Dr. Qiu Zhang Prof. Fujun Li Prof. Jun Chen 《Angewandte Chemie (International ed. in English)》2023,62(7):e202216047
Organic electrode materials have application potential in lithium batteries owing to their high capacity, abundant resources, and structural designability. However, most reported organic cathodes are at oxidized states (namely unlithiated compounds) and thus need to couple with Li-rich anodes. In contrast, lithiated organic cathode materials could act as a Li reservoir and match with Li-free anodes such as graphite, showing great promise for practical full-battery applications. Here we summarize the synthesis, stability, and battery applications of lithiated organic cathode materials, including synthetic methods, stability against O2 and H2O in air, and strategies to improve comprehensive electrochemical performance. Future research should be focused on new redox chemistries and the construction of full batteries with lithiated organic cathodes and commercial anodes under practical conditions. This Minireview will encourage more efforts on lithiated organic cathode materials and finally promote their commercialization. 相似文献
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Dr. Xinyu Guan Fengqian Chen Prof. Dr. Shilun Qiu Prof. Dr. Qianrong Fang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2023,135(3):e202213203
Three-dimensional covalent organic frameworks (3D COFs) with spatially periodic networks demonstrate significant advantages over their 2D counterparts, including enhanced specific surface areas, interconnected channels, and more sufficiently exposed active sites. Nevertheless, research on these materials has met an impasse due to serious problems in crystallization and stability, which must be solved for practical applications. In this Minireview, we first summarize some strategies for preparing functional 3D COFs, including crystallization techniques and functionalization methods. Hereafter, applications of these functional materials are presented, covering adsorption, separation, catalysis, fluorescence, sensing, and batteries. Finally, the future challenges and perspectives for the development of 3D COFs are discussed. 相似文献
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Sun Young Kim Minjung Kang Dr. Dong Won Kang Hyojin Kim Jong Hyeak Choe Hongryeol Yun Prof. Chang Seop Hong 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2023,135(2):e202214301
We proposed a new strategy to maximize the density of acidic groups by modulating the electronic effects of the substituents for high-performance proton conductors. The conductivity of the sulfonated 1-MeL40-S with methyl group corresponds to 2.29×10−1 S cm−1 at 80 °C and 90 % relative humidity, remarkably an 22100-fold enhancement over the nonsulfonated 1-MeL40 . 1-MeL40-S maintains long-term conductivity for one month. We confirm that this synthetic method is generalized to the extended version POPs, 2-MeL40-S and 3-MeL40-S . In particular, the conductivities of the POPs compete with those of top-level porous organic conductors. Moreover, the activation energy of the POPs is lower than that of the top-performing materials. This study demonstrates that systematic alteration of the electronic effects of substituents is a useful route to improve the conductivity and long-term durability of proton-conducting materials. 相似文献
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Dr. Yincai Xu Qingyang Wang Xinliang Cai Prof. Chenglong Li Prof. Shimei Jiang Prof. Yue Wang 《Angewandte Chemie (International ed. in English)》2023,62(52):e202312451
It is of great strategic significance to develop highly efficient narrowband organic electroluminescent materials that can be utilized to manufacture ultra-high-definition (UHD) displays and meet or approach the requirements of Broadcast Television 2020 (B.T.2020) color gamut standards. This motif poses challenges for molecular design and synthesis, especially for developing generality, diversity, scalability, and robustness of molecular structures. The emergence of multiple resonance thermally activated delayed fluorescence (MR-TADF) emitters has ingeniously solved the problems and demonstrated bright application prospects in the field of UHD displays, sparking a research boom. This Minireview summarizes the research endeavors of narrowband organic electroluminescent materials, with emphasis on the tremendous contribution of frontier molecular orbital engineering (FMOE) strategy. It combines the outstanding advantages of MR framework and donor-acceptor (D−A) structure, and can achieve red-shift and narrowband emission simultaneously, which is of great significance in the development of long-wavelength narrowband emitters with emission maxima especially exceeding 500 nm. We hope that this Minireview would provide some inspiration for what could transpire in the future. 相似文献
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无机多孔材料因其具有特殊的物化性能在化工、能源、环保等相关领域被广泛应用。本文总结了无机多孔材料的当前研究进展,详细介绍了微孔、介孔、大孔材料和大孔-介孔、大孔-微孔、介孔-微孔以及大孔-介孔-微孔等复合孔材料的制备方法,并介绍了无机多孔材料在室内、外等环保催化领域的应用,特别介绍了多孔材料对于消除移动源污染的应用。最后,对当前无机多孔材料在制备方面存在的问题进行了总结,并对今后无机多孔材料的制备方法和研究方向进行了展望。 相似文献
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疏水多孔硅制备及其对水中有机污染物的吸附 总被引:1,自引:0,他引:1
以硅酸钠为硅源,盐酸为催化剂,三甲基氯硅烷(TMCS)为表面改性剂,经溶胶-凝胶和表面改性过程制备出一种疏水性多孔硅材料.采用傅里叶变换红外(FTIR)光谱仪、接触角分析仪、氮气物理吸附仪和扫描电子显微镜(SEM)对其结构和性质进行表征.结果表明:所制备的多孔硅具有分等级孔道结构(中孔-大孔),比表面积为566m2·g-1,孔体积高达2.28cm3·g-1,多孔硅与水的接触角为156°,显示出超疏水特征.对甲苯、汽油、柴油和润滑油的吸附量均可高达自身质量的14倍,丰富的孔道使其在几分钟内即可达到饱和吸附.这种多孔硅在汽油/水混合体系中对汽油具有较高的选择性,同时具有良好的再生能力.经正己烷萃取再生后,多孔硅仍能基本保持初始吸附容量.此方法制备的多孔硅材料在吸附分离污水中的有机物和溢油处理方面具有很好的应用前景. 相似文献