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991.
992.
A novel synthesized Ag/C fibrous catalyst based on in situ thermally induced redox reaction of PVA/AgNO3 composite fibers was proposed. Utilizing the plasticization and complexation of AgNO3 solution, the melt spinning of PVA/AgNO3 composites was accomplished. Through the in situ thermally induced redox reaction on PVA/AgNO3 composite fibers combined with carbonization of PVA and reduction of Ag+, the synthesized Ag/C fibrous catalyst was prepared with nanosilver particles with average diameter of 130 nm immobilized on the loose microstructural carbon layers. The synthesized Ag/C fibrous catalyst exhibited excellent catalytic activity and reused for at least five cycles for the reduction of 4‐nitrophenol, which may hold great promise in effective and eco‐friendly waste water treatment. 相似文献
993.
Yan Meng Ziyin Kong James P. Morken 《Angewandte Chemie (International ed. in English)》2020,59(22):8456-8459
Chiral 1,2‐bimetallic reagents are useful motifs in synthetic chemistry. Although syn‐1,2‐bimetallic compounds can be prepared by alkene dimetallation, anti‐1,2‐bimetallics are still rare. The stereospecific 1,2‐metallate shift that occurs during conjunctive cross‐coupling is shown to enable a practical and modular approach to the catalytic synthesis of enantioenriched anti‐1,2‐borosilanes. In addition to reaction development, the synthetic utility of anti‐1,2‐borosilanes was investigated, including applications to the synthesis of anti‐1,2‐diols and anti‐1,2‐amino alcohols 相似文献
994.
Long‐Zhang Dong Lei Zhang Jiang Liu Qing Huang Meng Lu Wen‐Xin Ji Ya‐Qian Lan 《Angewandte Chemie (International ed. in English)》2020,59(7):2659-2663
A series of stable heterometallic Fe2M cluster‐based MOFs ( NNU‐31‐M , M=Co, Ni, Zn) photocatalysts are presented. They can achieve the overall conversion of CO2 and H2O into HCOOH and O2 without the assistance of additional sacrificial agent and photosensitizer. The heterometallic cluster units and photosensitive ligands excited by visible light generate separated electrons and holes. Then, low‐valent metal M accepts electrons to reduce CO2, and high‐valent Fe uses holes to oxidize H2O. This is the first MOF photocatalyst system to finish artificial photosynthetic full reaction. It is noted that NNU‐31‐Zn exhibits the highest HCOOH yield of 26.3 μmol g?1 h?1 (selectivity of ca. 100 %). Furthermore, the DFT calculations based on crystal structures demonstrate the photocatalytic reaction mechanism. This work proposes a new strategy for how to design crystalline photocatalyst to realize artificial photosynthetic overall reaction. 相似文献
995.
Jun‐Chao Liu Wei‐Qiang Liao Peng‐Fei Li Yuan‐Yuan Tang Xiao‐Gang Chen Xian‐Jiang Song Han‐Yue Zhang Yi Zhang Yu‐Meng You Ren‐Gen Xiong 《Angewandte Chemie (International ed. in English)》2020,59(9):3495-3499
Molecular ferroelectrics have attracted considerable interests because of their easy and environmentally friendly processing, low acoustical impedance and mechanical flexibility. Herein, a molecular thermochromic ferroelectric, N,N′‐dimethyl‐1,4‐diazoniabicyclo[2.2.2]octonium tetrachlorocuprate(II) ([DMe‐DABCO]CuCl4) is reported, which shows both excellent ferroelectricity and intriguing thermochromism. [DMe‐DABCO]CuCl4 undergoes a ferroelectric phase transition from Pca21 to Pbcm at a significantly high Curie temperature of 413 K, accompanied by a color change from yellow to red that is due to the remarkable deformation of [CuCl4]2? tetrahedron, where the ferroelectric and paraelectric phases correspond to yellow and red, respectively. Combined with multiple bistable physical properties, [DMe‐DABCO]CuCl4 would be a promising candidate for next‐generation smart devices, and should inspire further exploration of multifunctional molecular ferroelectrics. 相似文献
996.
Xixiong Jin Rongyan Wang Lingxia Zhang Rui Si Meng Shen Min Wang Jianjian Tian Jianlin Shi 《Angewandte Chemie (International ed. in English)》2020,59(17):6827-6831
The emerging metal single‐atom catalyst has aroused extensive attention in multiple fields, such as clean energy, environmental protection, and biomedicine. Unfortunately, though it has been shown to be highly active, the origins of the activity of the single‐atom sites remain unrevealed to date owing to the lack of deep insight on electronic level. Now, partially oxidized Ni single‐atom sites were constructed in polymeric carbon nitride (CN), which elevates the photocatalytic performance by over 30‐fold. The 3d orbital of the partially oxidized Ni single‐atom sites is filled with unpaired d‐electrons, which are ready to be excited under irradiation. Such an electron configuration results in elevated light response, conductivity, charge separation, and mobility of the photocatalyst concurrently, thus largely augmenting the photocatalytic performance. 相似文献
997.
Hongfeng Li Peng Wu Yawen Xiao Meng Shao Yu Shen Yun Fan Huanhuan Chen Ruijie Xie Wenlei Zhang Sheng Li Jiansheng Wu Yu Fu Bing Zheng Weina Zhang Fengwei Huo 《Angewandte Chemie (International ed. in English)》2020,59(12):4763-4769
Metal–organic frameworks (MOFs) are promising materials with fascinating properties. Their widespread applications are sometimes hindered by the intrinsic instability of frameworks. However, this instability of MOFs can also be exploited for useful purposes. Herein, we report the use of MOFs as metal ion precursors for constructing functional nanocomposites by utilizing the instability of MOFs. The heterogeneous growth process of nanostructures on substrates involves the release of metal ions, nucleation on substrates, and formation of a covering structure. Specifically, the synthesized CoS with carbon nanotubes as substrates display enhanced performance in a lithium‐ion battery. Such strategy not only presents a new way for exploiting the instability of MOFs but also supplies a prospect for designing versatile functional nanocomposites. 相似文献
998.
Jing Zhang Meng Liu Chuanhua Wu Gaoyuan Zhao Peiqi Chen Lin Zhou Xingang Xie Ran Fang Huilin Li Xuegong She 《Angewandte Chemie (International ed. in English)》2020,59(10):3966-3970
The first total synthesis of the Euphorbia diterpenoid pepluanol B in both racemic and enantioenriched form involves 20 steps from a known bicyclic diol. This synthesis features an unprecedented bromo‐epoxidation to control the eight‐membered‐ring conformation. In addition, salient reactions for the construction of the tetracyclic backbone include a sterically challenging aldol reaction to establish the quaternary center, a ring closing metathesis (RCM) to forge the eight‐membered ring, and a diastereoselective cyclopropanation to assemble the embedded cyclopropane motif. 相似文献
999.
Mimi Wan Qi Wang Xiaoyun Li Bo Xu Dan Fang Ting Li Yueqi Yu Leyi Fang Yue Wang Meng Wang Fenghe Wang Chun Mao Jian Shen Jia Wei 《Angewandte Chemie (International ed. in English)》2020,59(34):14458-14465
Limited tumor permeability of therapeutic agents is a great challenge faced by current cancer therapy methods. Herein, a kind of near infrared light (NIR)‐driven nanomotor with autonomous movement, targeted ability, hierarchical porous structure, multi‐drugs for cancer chemo/photothermal therapy is designed, prepared and characterized. Further, we establish a method to study the interaction between nanomotors and cells, along with their tumor permeability mechanism, including 2D cellular models, 3D multicellular tumor spheroids and in vivo models. In vivo tumor elimination results verify that the movement behaviour of the nanomotors can greatly facilitate them to eliminate tumor through multiple therapeutic methods. This work tries to establish systematic research and evaluation models, providing strategies to understand the relationship between motion behaviour and tumor permeation efficiency of nanomotors in depth. 相似文献
1000.
Jiajia Ru Ting He Binjie Chen Yutong Feng Lianhai Zu Zhijun Wang Qiaobao Zhang Tianzi Hao Ruijin Meng Renchao Che Chi Zhang Jinhu Yang 《Angewandte Chemie (International ed. in English)》2020,59(34):14621-14627
Weak van der Waals interactions between interlayers of two‐dimensional layered materials result in disabled across‐interlayer electron transfer and poor layered structural stability, seriously deteriorating their performance in energy applications. Herein, we propose a novel covalent assembly strategy for MoS2 nanosheets to realize unique MoS2/SnS hollow superassemblies (HSs) by using SnS nanodots as covalent linkages. The covalent assembly based on all‐inorganic and carbon‐free concept enables effective across‐interlayer electron transfer, facilitated ion diffusion kinetics, and outstanding mechanical stability, which are evidenced by experimental characterization, DFT calculations, and mechanical simulations. Consequently, the MoS2/SnS HSs exhibit superb rate performance and long cycling stability in lithium‐ion batteries, representing the best comprehensive performance in carbon‐free MoS2‐based anodes to date. Moreover, the MoS2/SnS HSs also show excellent sodium storage performance in sodium‐ion batteries. 相似文献