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Back Cover: A Highly‐Ordered 3D Covalent Fullerene Framework (Angew. Chem. Int. Ed. 26/2015) 下载免费PDF全文
Norma K. Minar Dr. Kun Hou Christian Westermeier Dr. Markus Döblinger Dr. Jörg Schuster Fabian C. Hanusch Dr. Bert Nickel Prof. Dr. Geoffrey A. Ozin Prof. Dr. Thomas Bein 《Angewandte Chemie (International ed. in English)》2015,54(26):7718-7718
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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
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Charlotte E. Boott Dr. Ali Nazemi Prof. Ian Manners 《Angewandte Chemie (International ed. in English)》2015,54(47):13876-13894
The creation of synthetic 2D materials represents an attractive challenge that is ultimately driven by their prospective uses in, for example, electronics, biomedicine, catalysis, sensing, and as membranes for separation and filtration. This Review illustrates some recent advances in this diverse field with a focus on covalent and non‐covalent 2D polymers and frameworks, and self‐assembled 2D materials derived from nanoparticles, homopolymers, and block copolymers. 相似文献
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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
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Highly Ordered Mesoporous Few‐Layer Graphene Frameworks Enabled by Fe3O4 Nanocrystal Superlattices 下载免费PDF全文
Yucong Jiao Dandan Han Limin Liu Li Ji Guannan Guo Prof. Jianhua Hu Prof. Dong Yang Prof. Angang Dong 《Angewandte Chemie (International ed. in English)》2015,54(19):5727-5731
While great progress has been achieved in the synthesis of ordered mesoporous carbons in the past decade, it still remains a challenge to prepare highly graphitic frameworks with ordered mesoporosity and high surface area. Reported herein is a simple synthetic methodology, based on the conversion of self‐assembled superlattices of Fe3O4 nanocrystals, to fabricate highly ordered mesoporous graphene frameworks (MGFs) with ultrathin pore walls consisting of three to six stacking graphene layers. The MGFs possess face‐centered‐cubic symmetry with interconnected mesoporosity, tunable pore width, and high surface area. Because of their unique architectures and superior structural durability, the MGFs exhibit excellent cycling stability and rate performance when used as anode materials for lithium‐ion batteries, thus retaining a specific capacity of 520 mAh g?1 at a current density of 300 mA g?1 after 400 cycles. 相似文献
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Ning Huang Dr. Xuesong Ding Dr. Jangbae Kim Prof. Dr. Hyotcherl Ihee Prof. Dr. Donglin Jiang 《Angewandte Chemie (International ed. in English)》2015,54(30):8704-8707
Ordered π‐columnar structures found in covalent organic frameworks (COFs) render them attractive as smart materials. However, external‐stimuli‐responsive COFs have not been explored. Here we report the design and synthesis of a photoresponsive COF with anthracene units as the photoresponsive π‐building blocks. The COF is switchable upon photoirradiation to yield a concavo‐convex polygon skeleton through the interlayer [4π+4π] cycloaddition of anthracene units stacked in the π‐columns. This cycloaddition reaction is thermally reversible; heating resets the anthracene layers and regenerates the COF. These external‐stimuli‐induced structural transformations are accompanied by profound changes in properties, including gas adsorption, π‐electronic function, and luminescence. The results suggest that COFs are useful for designing smart porous materials with properties that are controllable by external stimuli. 相似文献
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Norihiro Mizoshita Dr. Yasutomo Goto Dr. Mahendra P. Kapoor Dr. Toyoshi Shimada Prof. Dr. Takao Tani Dr. Shinji Inagaki Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(1):219-226
We report that 2,6‐naphthylene‐bridged periodic mesoporous organosilicas exhibit unique fluorescence behavior that reflects molecular‐scale periodicities in the framework. Periodic mesoporous organosilicas consisting of naphthalene–silica hybrid frameworks were synthesized by hydrolysis and condensation of a naphthalene‐derived organosilane precursor in the presence of a template surfactant. The morphologies and meso‐ and molecular‐scale periodicities of the organosilica materials strongly depend on the synthetic conditions. The naphthalene moieties embedded within the molecularly ordered framework exhibited a monomer‐band emission, whereas those embedded within the amorphous framework showed a broad emission attributed to an excimer band. These results suggest that the naphthalene moieties fixed within the crystal‐like framework are isolated in spite of their densely packed structure, different from conventional organosilica frameworks in which only excimer emission was observed for both the crystal‐like and amorphous frameworks at room temperature. This key finding suggests a potential to control interactions between organic groups and thus the optical properties of inorganic/organic hybrids. 相似文献
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Conductive Microporous Covalent Triazine‐Based Framework for High‐Performance Electrochemical Capacitive Energy Storage 下载免费PDF全文
Yajuan Li Shuanghao Zheng Xue Liu Pan Li Dr. Lei Sun Ruixia Yang Sen Wang Prof. Dr. Zhong‐Shuai Wu Prof. Dr. Xinhe Bao Prof. Dr. Wei‐Qiao Deng 《Angewandte Chemie (International ed. in English)》2018,57(27):7992-7996
Nitrogen‐enriched porous nanocarbon, graphene, and conductive polymers attract increasing attention for application in supercapacitors. However, electrode materials with a large specific surface area (SSA) and a high nitrogen doping concentration, which is needed for excellent supercapacitors, has not been achieved thus far. Herein, we developed a class of tetracyanoquinodimethane‐derived conductive microporous covalent triazine‐based frameworks (TCNQ‐CTFs) with both high nitrogen content (>8 %) and large SSA (>3600 m2 g?1). These CTFs exhibited excellent specific capacitances with the highest value exceeding 380 F g?1, considerable energy density of 42.8 Wh kg?1, and remarkable cycling stability without any capacitance degradation after 10 000 cycles. This class of CTFs should hold a great potential as high‐performance electrode material for electrochemical energy‐storage systems. 相似文献
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Dr. Régis Y. N. Gengler Prof. Dr. Dimitrios Gournis Akfiny H. Aimon Dr. Luminita M. Toma Prof. Dr. Petra Rudolf 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(24):7594-7600
Much of the research effort concerning the nanoscopic properties of clays has focused on its mechanical applications, for example, as nanofillers for polymer reinforcement. To broaden the horizon of what is possible by exploiting the richness of clays in nanoscience, herein we report a bottom‐up approach for the production of hybrid materials in which clays act as the structure‐directing interface and reaction media. This new method, which combines self‐assembly with the Langmuir–Schaefer technique, uses the clay nanosheets as a template for the grafting of C60 into a bi‐dimensional array, and allows for perfect layer‐by‐layer growth with control at the molecular level. In contrast to the more‐common growth of C60 arrays through nanopatterning, our approach can be performed under atmospheric conditions, can be upscaled to areas of tenths of cm2, and can be applied to almost any hydrophobic substrate. Herein, we report a detailed study of this approach by using temperature‐dependent X‐ray diffraction, spectroscopic measurements, and STM. 相似文献
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Direct On‐Surface Patterning of a Crystalline Laminar Covalent Organic Framework Synthesized at Room Temperature 下载免费PDF全文
Alejandro de la Peña Ruigómez David Rodríguez‐San‐Miguel Dr. Kyriakos C. Stylianou Dr. Massimiliano Cavallini Dr. Denis Gentili Dr. Fabiola Liscio Prof. Silvia Milita Dr. Otello Maria Roscioni Dr. Maria Luisa Ruiz‐González Carlos Carbonell Prof. Daniel Maspoch Dr. Rubén Mas‐Ballesté Dr. José Luis Segura Dr. Félix Zamora 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(30):10666-10670
We report herein an efficient, fast, and simple synthesis of an imine‐based covalent organic framework (COF) at room temperature (hereafter, RT‐COF‐1 ). RT‐COF‐1 shows a layered hexagonal structure exhibiting channels, is robust, and is porous to N2 and CO2. The room‐temperature synthesis has enabled us to fabricate and position low‐cost micro‐ and submicropatterns of RT‐COF‐1 on several surfaces, including solid SiO2 substrates and flexible acetate paper, by using lithographically controlled wetting and conventional ink‐jet printing. 相似文献
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Manfred Scheer Prof. Dr. Andrea Schindler Dipl.‐Chem. Christian Gröger Dr. Alexander V. Virovets Dr. Eugenia V. Peresypkina Dr. 《Angewandte Chemie (International ed. in English)》2009,48(27):5046-5049
The complete encapsulation of ortho‐carborane by a fullerene‐like building‐block system consisting of pentaphosphaferrocene and CuICl leads to the formation of the spherical supermolecule C2B10H12§[{Cp*Fe(η5‐P5)}12(CuCl)20]. This product of template‐controlled aggregation represents the first example of a carbon‐free C80 analogue possessing icosahedral symmetry.
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Symmetry versus Minimal Pentagonal Adjacencies in Uranium‐Based Polyoxometalate Fullerene Topologies
Ginger E. Sigmon Daniel K. Unruh Jie Ling Brittany Weaver Matthew Ward Laura Pressprich Antonio Simonetti Prof. Peter C. Burns Prof. 《Angewandte Chemie (International ed. in English)》2009,48(15):2737-2740
C U soon : Clusters containing 60, 44, and 36 uranyl peroxide hydroxide polyhedra (see picture) adopt fullerene topologies of maximum symmetry. The largest of these, denoted U60, is topologically identical to C60 with no pentagonal adjacencies and the highest possible symmetry. U44 adopts the topology with maximum symmetry rather than that with the lowest number of pentagonal adjacencies.