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81.
Heptagon‐Embedded Pentacene: Synthesis,Structures, and Thin‐Film Transistors of Dibenzo[d,d′]benzo[1,2‐a:4,5‐a′]dicycloheptenes 下载免费PDF全文
Xuejin Yang Danqing Liu Prof. Qian Miao 《Angewandte Chemie (International ed. in English)》2014,53(26):6786-6790
This study presents a new class of conjugated polycyclic molecules that contain seven‐membered rings, detailing their synthesis, crystal structures and semiconductor properties. These molecules have a nearly flat C6‐C7‐C6‐C7‐C6 polycyclic framework with a p‐quinodimethane core. With field‐effect mobilities of up to 0.76 cm2 V?1 s?1 as measured from solution‐processed thin‐film transistors, these molecules are alternatives to the well‐studied pentacene analogues for applications in organic electronic devices. 相似文献
82.
Dr. Ryo Tsunashima Yoshifumi Iwamoto Yusuke Baba Chisato Kato Katsuya Ichihashi Dr. Sadafumi Nishihara Prof. Katsuya Inoue Prof. Katsuya Ishiguro Prof. Yu‐Fei Song Prof. Tomoyuki Akutagawa 《Angewandte Chemie (International ed. in English)》2014,53(42):11228-11231
In a mixed‐valence polyoxometalate, electrons are usually delocalized within the cluster anion because of low level of inter‐cluster interaction. Herein, we report the structure and electrical properties of a single crystal in which mixed‐valence polyoxometalates were electrically wired by cationic π‐molecules of tetrathiafulvalene substituted with pyridinium. Electron‐transport characteristics are suggested to represent electron hopping through strong interactions between cluster and cationic π‐molecules. 相似文献
83.
A new Cu(Ⅱ) coordination polymer, [Cu2(mip)2(bmix)]n(bmix = 1,4-bis(2-methylimidazole-1-ylmethyl)benzene, H2 mip = 5-methylisophthalic acid), has been hydrothermally synthesized and characterized by elemental analyses, IR, TGA and single-crystal X-ray diffraction. The title compound belongs to the triclinic system, space group P1 with a = 9.435(5), b = 12.241(6), c = 13.666(6), β = 94.396(8)o, V = 1565.5(13) 3, Z = 2, C34H30Cu2N4O8, Mr = 749.70, Dc = 1.590 g/cm3, μ = 1.419 mm-1 and F(000) = 768. The title metal-organic coordination polymer exhibits the first two-fold interpenetrated pcu topological structure assembled by two types of dinuclear copper(Ⅱ) clusters and a flexible bis(imidazole)-based ligand. In addition, the fluorescence and catalytic performances of the complex for the degradation of Congo red azo dye in Fenton-like process were presented. 相似文献
84.
Haipeng B. Li Behabitu E. Tebikachew Cedrik Wiberg Kasper Moth-Poulsen Joshua Hihath 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(28):11738-11743
The exponential proliferation of data during the information age has required the continuous exploration of novel storage paradigms, materials, and devices with increasing data density. As a step toward the ultimate limits in data density, the development of an electrically controllable single-molecule memristive element is reported. In this device, digital information is encoded through switching between two isomer states by applying a voltage signal to the molecular junction, and the information is read out by monitoring the electrical conductance of each isomer. The two states are cycled using an electrically controllable local-heating mechanism for the forward reaction and catalyzed by a single charge-transfer process for the reverse switching. This single-molecule device can be modulated in situ, is fully reversible, and does not display stochastic switching. The I–V curves of this single-molecule system also exhibit memristive character. These features suggest a new approach for the development of molecular switching systems and storage-class memories. 相似文献
85.
Yuebin Lian Wenjuan Yang Chufeng Zhang Hao Sun Zhao Deng Wenjie Xu Li Song Zhongwen Ouyang Zhenxing Wang Jun Guo Yang Peng 《Angewandte Chemie (International ed. in English)》2020,59(1):286-294
Reversible oxygen conversion is important for various green energy technologies. Herein we synthesize a series of bimetallic coordination polymers by varying the Ni/Co ratio and using HITP (HITP=2,3,6,7,10,11‐hexaiminotriphenylene) as the ligand, to interrogate the role of metal centres in modulating the activity of the oxygen reduction reaction (ORR). Co3HITP2 and Ni3HITP2 are compared. Unpaired 3d electrons in Co3HITP2 result in less coplanarity but more radical character. Thus, despite of a reduced crystallinity and conductivity, the best ORR activity, comparable to 20 % Pt/C, is obtained for Co3HITP2, showing the 3d orbital configuration of the metal centre promotes ORR. Experimental and DFT studies show a transition of ORR pathway from four‐electron for Co3HITP2 to two‐electron for Ni3HITP2. Rechargeable zinc–air batteries using Co3HITP2 as the air cathode catalyst demonstrate excellent energy efficiency and stability. 相似文献
86.
Yunyu Sun Mingcheng Yang Yutong Guo Mengjiao Cheng Bin Dong Feng Shi 《Angewandte Chemie (International ed. in English)》2020,59(3):1098-1102
Light‐driven micropumps, which are based on electro‐osmosis with the electric field generated by photocatalytic reactions, are among most attractive research topics in chemical micromotors. Until now, research in this field has mainly been focused on the directional motion or collective behavior of microparticles, which lack practical applications. In this study, we have developed a photowelding strategy for repeated photoinduced conductivity recovery of cracked flexible circuits. We immersed the circuit in a suspension of conductive healing particles and applied photoillumination to the crack; photocatalysis of a predeposited pentacene (PEN) layer triggered electro‐osmotic effects to gather conductive particles at the crack, thus leading to conductivity recovery of the circuit. This photowelding strategy is a novel application of light‐driven micropumps and photocatalysis for conductivity restoration. 相似文献
87.
D. Thao Nguyen Matthias Freitag Christian Gutheil Kai Sotthewes Bonnie J. Tyler Marcus Bckmann Mowpriya Das Friederike Schlüter Nikos L. Doltsinis Heinrich F. Arlinghaus Bart Jan Ravoo Frank Glorius 《Angewandte Chemie (International ed. in English)》2020,59(32):13651-13656
A novel photoresponsive and fully conjugated N‐heterocyclic carbene (NHC) has been synthesized that combines the excellent photophysical properties of arylazopyrazoles (AAPs) with an NHC that acts as a robust surface anchor (AAP‐BIMe). The formation of self‐assembled monolayers (SAMs) on gold was proven by ToF‐SIMS and XPS, and the organic film displayed a very high stability at elevated temperatures. This stability was also reflected in a high desorption energy, which was determined by temperature‐programmed SIMS measurements. E‐/Z‐AAP‐BIMe@Au photoisomerization resulted in reversible alterations of the surface energy (i.e. wettability), the surface potential (i.e. work function), and the conductance (i.e. resistance). The effects could be explained by the difference in the dipole moment of the isomers. Furthermore, sequential application of a dummy ligand by microcontact printing and subsequent backfilling with AAP‐BIMe allowed its patterning on gold. To the best of our knowledge, this is the first example of a photoswitchable NHC on a gold surface. These properties of AAP‐BIMe@Au illustrate its suitability as a molecular switch for electronic devices. 相似文献
88.
Philipp Wilhelm Dominik Blank Prof. John M. Lupton Dr. Jan Vogelsang 《Chemphyschem》2020,21(10):961-965
Controlling the morphology of π-conjugated polymers for organic optoelectronic devices has long been a goal in the field of materials science. Since the morphology of a polymer chain is closely intertwined with its photophysical properties, it is desirable to be able to change the arrangement of the polymers at will. We investigate the π-conjugated polymer poly(9,9-dioctylfluorene) (PFO), which can exist in three distinctly different structural phases: the α-, β-, and γ-phase. Every phase has a different chain structure and a unique photoluminescence (PL) spectrum. Due to its unique properties and the pronounced spectral structure-property relations, PFO can be used as a model system to study the morphology of π-conjugated polymers. To avoid ensemble averaging, we examine the PL spectrum of single PFO chains embedded in a non-fluorescent matrix. With single-molecule spectroscopy the structural phase of every single chain can be determined, and changes can be monitored very easily. To manipulate the morphology, solvent vapor annealing (SVA) was applied, which leads to a diffusion of the polymer chains in the matrix. The β- and γ-phases appear during the self-assembly of single α-phase PFO chains into mesoscopic aggregates. The extent of β- and γ-phase formation is directed by the solvent-swelling protocol used for aggregation. Aggregation unequivocally promotes formation of the more planar β- and γ-phases. Once these lower-energy more ordered structural phases are formed, SVA cannot return the polymer chain to the less ordered phase by aggregate swelling. 相似文献
89.
Sang Kyu Park Hong Sun Hyunjoong Chung Bijal B. Patel Fengjiao Zhang Daniel W. Davies Toby J. Woods Kejie Zhao Ying Diao 《Angewandte Chemie (International ed. in English)》2020,59(31):13004-13012
Like silicon, single crystals of organic semiconductors are pursued to attain intrinsic charge transport properties. However, they are intolerant to mechanical deformation, impeding their application in flexible electronic devices. Such contradictory properties, namely exceptional molecular ordering and mechanical flexibility, are unified in this work. We found that bis(triisopropylsilylethynyl)pentacene (TIPS‐P) crystals can undergo mechanically induced structural transitions to exhibit superelasticity and ferroelasticity. These properties arise from cooperative and correlated molecular displacements and rotations in response to mechanical stress. By utilizing a bending‐induced ferroelastic transition of TIPS‐P, flexible single‐crystal electronic devices were obtained that can tolerate strains (?) of more than 13 % while maintaining the charge carrier mobility of unstrained crystals (μ>0.7 μ0). Our work will pave the way for high‐performance ultraflexible single‐crystal organic electronics for sensors, memories, and robotic applications. 相似文献
90.
Julien Warnan Erwin Reisner 《Angewandte Chemie (International ed. in English)》2020,59(40):17344-17354
From the understanding of biological processes and metalloenzymes to the development of inorganic catalysts, electro‐ and photocatalytic systems for fuel generation have evolved considerably during the last decades. Recently, organic and hybrid organic systems have emerged to challenge the classical inorganic structures through their enormous chemical diversity and modularity that led earlier to their success in organic (opto)electronics. This Minireview describes recent advances in the design of synthetic organic architectures and promising strategies toward (solar) fuel synthesis, highlighting progress on materials from organic ligands and chromophores to conjugated polymers and covalent organic frameworks. 相似文献