共查询到20条相似文献,搜索用时 15 毫秒
1.
Renhao Dong Martin Pfeffermann Haiwei Liang Zhikun Zheng Xiang Zhu Jian Zhang Xinliang Feng 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(41):12226-12231
The rational construction of covalent or noncovalent organic two‐dimensional nanosheets is a fascinating target because of their promising applications in electronics, membrane technology, catalysis, sensing, and energy technologies. Herein, a large‐area (square millimeters) and free‐standing 2D supramolecular polymer (2DSP) single‐layer sheet (0.7–0.9 nm in thickness), comprising triphenylene‐fused nickel bis(dithiolene) complexes has been readily prepared by using the Langmuir–Blodgett method. Such 2DSPs exhibit excellent electrocatalytic activities for hydrogen generation from water with a Tafel slope of 80.5 mV decade−1 and an overpotential of 333 mV at 10 mA cm−2, which are superior to that of recently reported carbon nanotube supported molecular catalysts and heteroatom‐doped graphene catalysts. This work is promising for the development of novel free‐standing organic 2D materials for energy technologies. 相似文献
2.
Gang Wang Chao Chen Yunhua Chen Xiongwu Kang Chenghao Yang Fei Wang Yong Liu Xunhui Xiong 《Angewandte Chemie (International ed. in English)》2020,59(5):2055-2060
Constructing a solid electrolyte interface (SEI) is a highly effective approach to overcome the poor reversibility of lithium (Li) metal anodes. Herein, an adhesive and self‐healable supramolecular copolymer, comprising of pendant poly(ethylene oxide) (PEO) segments and ureido‐pyrimidinone (UPy) quadruple‐hydrogen‐bonding moieties, is developed as a protection layer of Li anode by a simple drop‐coating. The protection performance of in‐situ‐formed LiPEO–UPy SEI layer is significantly enhanced owing to the strong binding and improved stability arising from a spontaneous reaction between UPy groups and Li metal. An ultrathin (approximately 70 nm) LiPEO–UPy layer can contribute to stable and dendrite‐free cycling at a high areal capacity of 10 mAh cm?2 at 5 mA cm?2 for 1000 h. This coating together with the promising electrochemical performance offers a new strategy for the development of dendrite‐free metal anodes. 相似文献
3.
Yuanxin Deng Qi Zhang Prof. Ben L. Feringa Prof. He Tian Prof. Da-Hui Qu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(13):5316-5321
Supramolecular polymers that can heal themselves automatically usually exhibit weakness in mechanical toughness and stretchability. Here we exploit a toughening strategy for a dynamic dry supramolecular network by introducing ionic cluster-enhanced iron-carboxylate complexes. The resulting dry supramolecular network simultaneous exhibits tough mechanical strength, high stretchability, self-healing ability, and processability at room temperature. The excellent performance of these distinct supramolecular polymers is attributed to the hierarchical existence of four types of dynamic combinations in the high-density dry network, including dynamic covalent disulfide bonds, noncovalent H-bonds, iron-carboxylate complexes and ionic clustering interactions. The extremely facile preparation method of this self-healing polymer offers prospects for high-performance low-cost material among others for coatings and wearable devices. 相似文献
4.
5.
6.
7.
8.
9.
Mickaël Mnand Sgolne AdamdeBeaumais Lise‐Marie Chamoreau Etienne Derat Sbastien Blanchard Yongmin Zhang Laurent Bouteiller Matthieu Sollogoub 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(28):7366-7370
The crystallization of a di‐azido‐α‐cyclodextrin revealed a polymeric self‐assembly involving a variety of azido‐type interactions. The crystal arrangement relies on the cooperativity of a primary azido inclusion, a secondary azido–azido interaction involving an unprecedented distribution of canonical forms, and a tertiary azido–groove interaction. The second azido group brings in a major contribution to the supramolecular structure illustrating the benefit of a difunctionalization for the generation of hierarchy. 相似文献
10.
11.
12.
13.
14.
Virgile Ayzac Quentin Sallembien Matthieu Raynal Benjamin Isare Jacques Jestin Laurent Bouteiller 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(39):13987-13991
Introduction of competing interactions in the design of a supramolecular polymer (SP) creates pathway complexity. Ester–bis‐ureas contain both a strong bis‐urea sticker that is responsible for the build‐up of long rod‐like objects by hydrogen bonding and ester groups that can interfere with this main pattern in a subtle way. Spectroscopic (FTIR and CD), calorimetric (DSC), and scattering (SANS) techniques show that such ester–bis‐ureas self‐assemble into three competing rod‐like SPs. The previously unreported low‐temperature SP is stabilized by hydrogen bonds between the interfering ester groups and the urea moieties. It also features a weak macroscopic alignment of the rods. The other structures form isotropic dispersions of rods stabilized by the more classical urea‐urea hydrogen bonding pattern. The transition from the low‐temperature structure to the next occurs reversibly by heating and is accompanied by an increase in viscosity, a rare feature for solutions in hydrocarbons. 相似文献
15.
Jun Sawada Daisuke Aoki Hideyuki Otsuka Toshikazu Takata 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(9):2791-2794
Three component mobility controlling vinylic rotaxane crosslinkers with two radically polymerizable vinyl groups ( RC_R s) were synthesized to prove that the mobility of the components of the RC_R s plays a crucial role in determining the properties of rotaxane‐crosslinked polymers (RCPs). RC_R s (R=H, Me, or Et) were obtained from living ring‐opening polymerization. RCP_Et was prepared using RC_Et , which exhibits the lowest component mobility. The low component mobility is reflected in inferior mechanical strength and stretching ability in tensile stress tests compared to components with good (R=Me) and high (R=H) mobility. However, RCP_Et exhibited significantly higher stress and strain values than the corresponding covalently crosslinked polymers ( CCP_R s). These results indicate that a suitable component mobility substantially enhances the mechanical strength of RCPs. This behavior could serve as a guiding principle for the molecular design of advanced RCs. 相似文献
16.
17.
18.
19.