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1.
Covalent organic frameworks (COFs) as an emerging type of crystalline porous materials, have obtained considerable attention recently. They have exhibited diverse structure and attractive performance in various catalytic reactions. It is highly expected to have a systematic and comprehensive review summing up COFs‐derived catalysts in homogeneous and heterogeneous catalysis, which is favorable to the judicious design of an efficient catalyst for targeted reaction. Herein, we focus on summarizing recent and significant developments in COFs materials, with an emphasis on both the synthetic strategies and targeted functionalization, and categorize it in accordance with the different types of catalytic reactions. Their potential catalysis applications are reviewed thoroughly. Moreover, a personal view about the future development of COFs catalysts with respect to the large‐scale production is also discussed. 相似文献
2.
3D Microporous Base‐Functionalized Covalent Organic Frameworks for Size‐Selective Catalysis 下载免费PDF全文
Dr. Qianrong Fang Dr. Shuang Gu Jie Zheng Dr. Zhongbin Zhuang Prof. Shilun Qiu Prof. Dr. Yushan Yan 《Angewandte Chemie (International ed. in English)》2014,53(11):2878-2882
The design and synthesis of 3D covalent organic frameworks (COFs) have been considered a challenge, and the demonstrated applications of 3D COFs have so far been limited to gas adsorption. Herein we describe the design and synthesis of two new 3D microporous base‐functionalized COFs, termed BF‐COF‐1 and BF‐COF‐2, by the use of a tetrahedral alkyl amine, 1,3,5,7‐tetraaminoadamantane (TAA), combined with 1,3,5‐triformylbenzene (TFB) or triformylphloroglucinol (TFP). As catalysts, both BF‐COFs showed remarkable conversion (96 % for BF‐COF‐1 and 98 % for BF‐COF‐2), high size selectivity, and good recyclability in base‐catalyzed Knoevenagel condensation reactions. This study suggests that porous functionalized 3D COFs could be a promising new class of shape‐selective catalysts. 相似文献
3.
Renata A. Maia Fabienne Berg Prof. Dr. Vincent Ritleng Dr. Benoît Louis Prof. Dr. Pierre M. Esteves 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(9):2051-2059
A series of nickel-decorated covalent organic frameworks, NiCl@RIO-12, were prepared using the post-synthetic modification strategy, that is, by reacting NiCl2 with pristine RIO-12 under alkaline conditions. Interestingly, they retained their crystallinity and the amount of nickel incorporated could be tuned from 3.6 to 25 wt % according to the reaction conditions. The incorporation of a higher amount of nickel in NiCl@RIO-12 consistently led to a lower Brunauer–Emmett–Teller surface area. Additionally, no agglomeration of nickel particles was found and a relatively homogeneous dispersion of nickel could be ascertained by SEM and TEM-EDS. The paramagnetic material exhibited promising catalytic activity in Suzuki–Miyaura cross-coupling under microwave heating. Thus, NiCl@RIO-12 notably demonstrated good thermal stability and its recyclability showed no substantial loss of activity after 3 cycles. 相似文献
4.
共价有机框架材料(covalent organic frameworks, COF)是功能材料领域研究的热点之一。COF具有孔道结构高度有序、孔径可调、比表面积较大、合成方法多样和易于功能化修饰等优点,是一类新兴的多相催化剂。目前,COF催化剂主要设计思路是:基于“自下而上”策略将非金属催化活性中心嵌入材料骨架来构筑本征型COF催化剂,或者以COF为载体,通过后修饰方式负载金属颗粒或离子构建多相催化剂。鉴于COF以上优势,预计COF催化剂在多相催化和手性催化领域中的应用也将取得更大的进展。本文综述了COF催化剂的合成和功能化策略,并展望了COF在多相催化领域中的应用前景。 相似文献
5.
Dan Chen Weiben Chen Dr. Guolong Xing Dr. Ting Zhang Prof. Long Chen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(38):8377-8381
A highly crystalline bicarbazole-based covalent organic framework (BCzP-COF) was synthesized via an upgraded “two-in-one” strategy by the self-polycondensation of A2B2 monomer with two neopentyl acetal and two amine groups. Such a strategy is propitious to afford higher crystallinity, larger special surface areas and better morphology than that of using unprotected monomer with free aldehydes and amines. Additionally, the off-white powder of BCzP-COF could serve as acidichromism sensor with a significant color change. Intriguingly, the conductivity of the protonated BCzP-COF can improve by six orders of magnitude compared to that of the pristine samples. This work has the potential to lead to bicarbazole-functional materials for chemosensors and electronic devices. 相似文献
6.
Dr. Jinqiao Dong Dr. Xing Han Prof. Yan Liu Dr. Haiyang Li Prof. Yong Cui 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(33):13826-13837
Many sophisticated chemical and physical properties of porous materials strongly rely on the presence of the metal ions within the structures. Whereas homogeneous distribution of metals is conveniently realized in metal–organic frameworks (MOFs), the limited stability potentially restricts their practical implementation. From that perspective, the development of metal–covalent organic frameworks (MCOFs) may address these shortcomings by incorporating active metal species atop highly stable COF backbones. This Minireview highlights examples of MCOFs that tackle important issues from their design, synthesis, characterization to cutting-edge applications. 相似文献
7.
Jinwei Zhao Junyu Ren Dr. Guang Zhang Dr. Ziqiang Zhao Prof. Shiyong Liu Prof. Wandong Zhang Prof. Long Chen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(42):10781-10797
Intermolecular charge transfer (ICT) effect has been widely studied in both small molecules and linear polymers. Covalently-bonded donor-acceptor pairs with tunable bandgaps and photoelectric properties endow these materials with potential applications in optoelectronics, fluorescent bioimaging, and sensors, etc. However, owing to the lack of charge transfer pathway or effective separation of charge carriers, unfavorable charge recombination gives rise to inevitable energy loss. Covalent organic frameworks (COFs) can be mediated with various geometry- and property-tailored building blocks, where donor (D) and acceptor (A) segments are connected by covalent bonds and can be finely arranged to form highly ordered networks (namely D−A COFs). The unique structural features of D−A COFs render the formation of segregated D−A stacks, thus provides pathways and channels for effective charge carriers transport. This review highlights the significant progress on D−A COFs over the past decade with emphasis on design principles, growing structural diversities, and promising application potentials. 相似文献
8.
Dr. Jin-Yue Zeng Xiao-Shuang Wang Prof. Dr. Xian-Zheng Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(70):16568-16581
Covalent organic frameworks (COFs) are an emerging kind of crystalline porous polymers that present the precise integration of organic building blocks into extensible structures with regular pores and periodic skeletons. The diversity of organic units and covalent linkages makes COFs a rising materials platform for the design of structure and functionality. Herein, recent research progress in developing COFs for photoluminescent materials is summarised. Structural and functional design strategies are highlighted and fundamental problems that need to be solved are identified, in conjunction with potential applications from perspectives of photoluminescent materials. 相似文献
9.
Ignacio Romero-Muñiz Dr. Andreas Mavrandonakis Pablo Albacete Alicia Vega Dr. Valérie Briois Prof. Félix Zamora Dr. Ana E. Platero-Prats 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(31):13113-13120
Layered covalent organic frameworks (2D-COFs), composed of reversible imine linkages and accessible pores, offer versatility for chemical modifications towards the development of catalytic materials. Nitrogen-enriched COFs are good candidates for binding Pd species. Understanding the local structure of reacting Pd sites bonded to the COF pores is key to rationalize interactions between active sites and porous surfaces. By combining advanced synchrotron characterization methods with periodic computational DFT modeling, the precise atomic structure of catalytic Pd sites attached to local defects is resolved within an archetypical imine-linked 2D-COF. This material was synthesized using an in situ method as a gel, under which imine hydrolysis and metalation reactions are coupled. Local defects formed in situ within imine-linked 2D-COF materials are highly reactive towards Pd metalation, resulting in active materials for Suzuki–Miyaura cross-coupling reactions. 相似文献
10.
Johannes Maschita Dr. Tanmay Banerjee Gökcen Savasci Dr. Frederik Haase Prof. Christian Ochsenfeld Prof. Bettina V. Lotsch 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(36):15880-15888
Covalent organic frameworks (COFs) are an extensively studied class of porous materials, which distinguish themselves from other porous polymers in their crystallinity and high degree of modularity, enabling a wide range of applications. COFs are most commonly synthesized solvothermally, which is often a time-consuming process and restricted to well-soluble precursor molecules. Synthesis of polyimide-linked COFs (PI-COFs) is further complicated by the poor reversibility of the ring-closing reaction under solvothermal conditions. Herein, we report the ionothermal synthesis of crystalline and porous PI-COFs in zinc chloride and eutectic salt mixtures. This synthesis does not require soluble precursors and the reaction time is significantly reduced as compared to standard solvothermal synthesis methods. In addition to applying the synthesis to previously reported imide COFs, a new perylene-based COF was also synthesized, which could not be obtained by the classical solvothermal route. In situ high-temperature XRPD analysis hints to the formation of precursor–salt adducts as crystalline intermediates, which then react with each other to form the COF. 相似文献
11.
Jinqiao Dong Xing Han Yan Liu Haiyang Li Yong Cui 《Angewandte Chemie (International ed. in English)》2020,59(33):13722-13733
Many sophisticated chemical and physical properties of porous materials strongly rely on the presence of the metal ions within the structures. Whereas homogeneous distribution of metals is conveniently realized in metal–organic frameworks (MOFs), the limited stability potentially restricts their practical implementation. From that perspective, the development of metal–covalent organic frameworks (MCOFs) may address these shortcomings by incorporating active metal species atop highly stable COF backbones. This Minireview highlights examples of MCOFs that tackle important issues from their design, synthesis, characterization to cutting‐edge applications. 相似文献
12.
Dr. Lipeng Zhai Dr. Siwen Cui Boli Tong Prof. Weihua Chen Dr. Zijie Wu Prof. Constantinos Soutis Prof. Donglin Jiang Prof. Guangshan Zhu Prof. Liwei Mi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(26):5784-5788
Covalent organic frameworks (COFs) enable precise integration of various organic building blocks into porous skeletons through topology predesign. Here, we report the first example of COFs by integrating electron withdrawing bromine group onto the skeletons for triboelectric nanogenerators (TENG). The resulting framework exhibits high surface area and good crystallinity. Thus, the bromine functionalized COF has more regular aligned π columns and arrays over the skeleton than bare COFs, which in turn significantly enhances charge transport ability. As a result, bromine functionalized COFs showed higher electrical output performance at 5 Hz with a peak value of short circuit current density of 43.6 μA and output voltage of 416 V, which is 2 and 1.3 times higher than those of bare COFs (21.6 μA and 318 V), respectively. These results demonstrated that this strategy for engineering electron withdrawing groups on the skeleton could open a new aspect of COFs for developing TENG devices. 相似文献
13.
Felipe L. Oliveira Dr. Stefania P. de Souza Dr. Jonathan Bassut Prof. Heiddy M. Álvarez Prof. Yunier Garcia-Basabe Prof. Rodrigo O. M. Alves de Souza Prof. Pierre M. Esteves Prof. Raoni S. B. Gonçalves 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(69):15863-15870
Sustainability in chemistry heavily relies on heterogeneous catalysis. Enzymes, the main catalyst for biochemical reactions in nature, are an elegant choice to catalyze reactions due to their high activity and selectivity, although they usually suffer from lack of robustness. To overcome this drawback, enzyme-decorated nanoporous heterogeneous catalysts were developed. Three different approaches for Candida antarctica lipase B (CAL-B) immobilization on a covalent organic framework (PPF-2) were employed: physical adsorption on the surface, covalent attachment of the enzyme in functional groups on the surface and covalent attachment into a linker added post-synthesis. The influence of the immobilization strategy on the enzyme uptake, specific activity, thermal stability, and the possibility of its use through multiple cycles was explored. High specific activities were observed for PPF-2-supported CAL-B in the esterification of oleic acid with ethanol, ranging from 58 to 283 U mg−1, which was 2.6 to 12.7 times greater than the observed for the commercial Novozyme 435. 相似文献
14.
Prof. Yanan Gao Chang Wang Dr. Hui Hu Dr. Rile Ge Meihuan Lu Jianqiang Zhang Zhongping Li Pengpeng Shao Prof. Donglin Jiang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(68):15488-15492
Two-dimensional covalent organic frameworks were synthesized in high yields by polycondensation in nonvolatile ionic liquids. The resulting crystallites are highly porous and exhibit exceptional capability of removing bisphenol A from water. The one reported is a general method to synthesize microporous and mesoporous frameworks, it allows to achieve regular macroscopic shapes, and it is effective in a wide range of reaction temperatures. 相似文献
15.
Covalent Organic Frameworks and Cage Compounds: Design and Applications of Polymeric and Discrete Organic Scaffolds 下载免费PDF全文
Priv.‐Doz. Dr. Florian Beuerle Dr. Bappaditya Gole 《Angewandte Chemie (International ed. in English)》2018,57(18):4850-4878
Porous organic materials are an emerging class of functional nanostructures with unprecedented properties. Dynamic covalent assembly of small organic building blocks under thermodynamic control is utilized for the intriguingly simple formation of complex molecular architectures in one‐pot procedures. In this Review, we aim to analyze the basic design principles that govern the formation of either covalent organic frameworks as crystalline porous polymers or covalent organic cage compounds as shape‐persistent molecular objects. Common synthetic procedures and characterization techniques will be discussed as well as more advanced strategies such as postsynthetic modification or self‐sorting. When appropriate, comparisons are drawn between polymeric frameworks and discrete organic cages in terms of their underlying properties. Furthermore, we highlight the potential of these materials for applications ranging from gas storage to catalysis and organic electronics. 相似文献
16.
Soraia P. S. Fernandes Dr. Vanesa Romero Dr. Begoña Espiña Dr. Laura M. Salonen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(26):6461-6473
Covalent organic frameworks (COFs) are attractive materials receiving increasing interest in the literature due to their crystallinity, large surface area, and pore uniformity. Their properties can be tailored towards specific applications by judicious design of COF building blocks, giving access to tailor-made pore sizes and surfaces. In this Concept article, developments in the field of COFs that have allowed these materials to be explored for contaminant adsorption are discussed. Strategies to obtain water-stable materials with highly ordered structures and large surface areas are reviewed. Post-synthetic modification approaches, by which pore surfaces can be tuned to target specific contaminants, are described. Recent advances in COF formulations, crucial for future implementation in adsorption devices, are highlighted. At the end, future challenges which need to be addressed to allow for the deployment of COFs for the capture of water contaminants will be discussed. 相似文献
17.
18.
Johannes Maschita Tanmay Banerjee Gkcen Savasci Frederik Haase Christian Ochsenfeld Bettina V. Lotsch 《Angewandte Chemie (International ed. in English)》2020,59(36):15750-15758
Covalent organic frameworks (COFs) are an extensively studied class of porous materials, which distinguish themselves from other porous polymers in their crystallinity and high degree of modularity, enabling a wide range of applications. COFs are most commonly synthesized solvothermally, which is often a time‐consuming process and restricted to well‐soluble precursor molecules. Synthesis of polyimide‐linked COFs (PI‐COFs) is further complicated by the poor reversibility of the ring‐closing reaction under solvothermal conditions. Herein, we report the ionothermal synthesis of crystalline and porous PI‐COFs in zinc chloride and eutectic salt mixtures. This synthesis does not require soluble precursors and the reaction time is significantly reduced as compared to standard solvothermal synthesis methods. In addition to applying the synthesis to previously reported imide COFs, a new perylene‐based COF was also synthesized, which could not be obtained by the classical solvothermal route. In situ high‐temperature XRPD analysis hints to the formation of precursor–salt adducts as crystalline intermediates, which then react with each other to form the COF. 相似文献
19.
Huimin Ding Yonghai Li Hui Hu Dr. Yimeng Sun Jianguo Wang Caixing Wang Prof. Dr. Cheng Wang Dr. Guanxin Zhang Prof. Dr. Baoshan Wang Prof. Dr. Wei Xu Prof. Dr. Deqing Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(45):14614-14618
Two‐dimensional covalent organic frameworks (2D COFs) provide a unique platform for the molecular design of electronic and optoelectronic materials. Here, the synthesis and characterization of an electroactive COF containing the well‐known tetrathiafulvalene (TTF) unit is reported. The TTF‐COF crystallizes into 2D sheets with an eclipsed AA stacking motif, and shows high thermal stability and permanent porosity. The presence of TTF units endows the TTF‐COF with electron‐donating ability, which is characterized by cyclic voltammetry. In addition, the open frameworks of TTF‐COF are amenable to doping with electron acceptors (e.g., iodine), and the conductivity of TTF‐COF bulk samples can be improved by doping. Our results open up a reliable route for the preparation of well‐ordered conjugated TTF polymers, which hold great potential for applications in fields from molecular electronics to energy storage. 相似文献
20.
Ignacio Romero‐Muiz Andreas Mavrandonakis Pablo Albacete Alicia Vega Valrie Briois Flix Zamora Ana E. Platero‐Prats 《Angewandte Chemie (International ed. in English)》2020,59(31):13013-13020
Layered covalent organic frameworks (2D‐COFs), composed of reversible imine linkages and accessible pores, offer versatility for chemical modifications towards the development of catalytic materials. Nitrogen‐enriched COFs are good candidates for binding Pd species. Understanding the local structure of reacting Pd sites bonded to the COF pores is key to rationalize interactions between active sites and porous surfaces. By combining advanced synchrotron characterization methods with periodic computational DFT modeling, the precise atomic structure of catalytic Pd sites attached to local defects is resolved within an archetypical imine‐linked 2D‐COF. This material was synthesized using an in situ method as a gel, under which imine hydrolysis and metalation reactions are coupled. Local defects formed in situ within imine‐linked 2D‐COF materials are highly reactive towards Pd metalation, resulting in active materials for Suzuki–Miyaura cross‐coupling reactions. 相似文献