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991.
Yulin Jie Xiaojing Liu Zhanwu Lei Shiyang Wang Yawei Chen Fanyang Huang Ruiguo Cao Genqiang Zhang Shuhong Jiao 《Angewandte Chemie (International ed. in English)》2020,59(9):3505-3510
Lithium metal is an ideal electrode material for future rechargeable lithium metal batteries. However, the widespread deployment of metallic lithium anode is significantly hindered by its dendritic growth and low Coulombic efficiency, especially in ester solvents. Herein, by rationally manipulating the electrolyte solvation structure with a high donor number solvent, enhancement of the solubility of lithium nitrate in an ester‐based electrolyte is successfully demonstrated, which enables high‐voltage lithium metal batteries. Remarkably, the electrolyte with a high concentration of LiNO3 additive presents an excellent Coulombic efficiency up to 98.8 % during stable galvanostatic lithium plating/stripping cycles. A full‐cell lithium metal battery with a lithium nickel manganese cobalt oxide cathode exhibits a stable cycling performance showing limited capacity decay. This approach provides an effective electrolyte manipulation strategy to develop high‐voltage lithium metal batteries. 相似文献
992.
Rui‐Ting Gao Dan He Lijun Wu Kan Hu Xianhu Liu Yiguo Su Lei Wang 《Angewandte Chemie (International ed. in English)》2020,59(15):6213-6218
Increasing long‐term photostability of BiVO4 photoelectrode is an important issue for solar water splitting. The NiOOH oxygen evolution catalyst (OEC) has fast water oxidation kinetics compared to the FeOOH OEC. However, it generally shows a lower photoresponse and poor stability because of the more substantial interface recombination at the NiOOH/BiVO4 junction. Herein, we utilize a plasma etching approach to reduce both interface/surface recombination at NiOOH/BiVO4 and NiOOH/electrolyte junctions. Further, adding Fe2+ into the borate buffer electrolyte alleviates the active but unstable character of etched‐NiOOH/BiVO4, leading to an outstanding oxygen evolution over 200 h. The improved charge transfer and photostability can be attributed to the active defects and a mixture of NiOOH/NiO/Ni in OEC induced by plasma etching. Metallic Ni acts as the ion source for the in situ generation of the NiFe OEC over long‐term durability. 相似文献
993.
Wen‐Wen Zhang Su‐Lei Zhang Bi‐Jie Li 《Angewandte Chemie (International ed. in English)》2020,59(17):6874-6880
Chiral propargyl amines are valuable synthetic intermediates for the preparation of biologically active compounds and functionalized amines. Catalytic methods to access propargyl amines containing vicinal stereocenters with high diastereoselectivity are particularly rare. We report an unprecedented strategy for the synthesis of enantioenriched propargyl amines with two stereogenic centres. An iridium complex, ligated by a phosphoramidite ligand, catalyzes the hydroalkynylation of β,β‐disubstituted enamides to afford propargyl amides in a highly regio‐, diastereo‐, and enantioselective fashion. Stereodivergent synthesis of all four possible stereoisomers was achieved using this strategy. 相似文献
994.
Hongjuan Zhang Yuchao Liang Hao Zhao Ruilian Qi Zhuo Chen Huanxiang Yuan Haiyan Liang Lei Wang 《Macromolecular bioscience》2020,20(2)
In this work, dual‐mode antibacterial conjugated polymer nanoparticles (DMCPNs) combined with photothermal therapy (PTT) and photodynamic therapy (PDT) are designed and explored for efficient killing of ampicillin‐resistant Escherichia coli (Ampr E. coli). The DMCPNs are self‐assembled into nanoparticles with a size of 50.4 ± 0.6 nm by co‐precipitation method using the photothermal agent poly(diketopyrrolopyrrole‐thienothiophene) (PDPPTT) and the photosensitizer poly[2‐methoxy‐5‐((2‐ethylhexyl)oxy)‐p‐phenylenevinylene] (MEH‐PPV) in the presence of poly(styrene‐co‐maleic anhydride) which makes nanoparticles disperse well in water via hydrophobic interactions. Thus, DMCPNs simultaneously possess photothermal effect and the ability of sensitizing oxygen in the surrounding to generate reactive oxygen species upon the illumination of light, which could easily damage resistant bacteria. Under combined irradiation of near‐infrared light (550 mW cm?2, 5 min) and white light (65 mW cm?2, 5 min), DMCPNs with a concentration of 9.6 × 10?4 µm could reach a 93% inhibition rate against Ampr E. coli, which is higher than the efficiency treated by PTT or PDT alone. The dual‐mode nanoparticles provide potential for treating pathogenic infections induced by resistant microorganisms in clinic. 相似文献
995.
Siyuan Li Weidong Zhang Qiang Wu Lei Fan Xinyang Wang Xiao Wang Zeyu Shen Yi He Yingying Lu 《Angewandte Chemie (International ed. in English)》2020,59(35):14935-14941
A rechargeable Li metal anode coupled with a high‐voltage cathode is a promising approach to high‐energy‐density batteries exceeding 300 Wh kg?1. Reported here is an advanced dual‐additive electrolyte containing a unique solvation structure and it comprises a tris(pentafluorophenyl)borane additive and LiNO3 in a carbonate‐based electrolyte. This system generates a robust outer Li2O solid electrolyte interface and F‐ and B‐containing conformal cathode electrolyte interphase. The resulting stable ion transport kinetics enables excellent cycling of Li/LiNi0.8Mn0.1Co0.1O2 for 140 cycles with 80 % capacity retention under highly challenging conditions (≈295.1 Wh kg?1 at cell‐level). The electrolyte also exhibits high cycling stability for a 4.6 V LiCoO2 (160 cycles with 89.8 % capacity retention) cathode and 4.95 V LiNi0.5Mn1.5O4 cathode. 相似文献
996.
Hongyun Ma Hongwu Chen Mingmao Wu Fengyao Chi Feng Liu Jiaxin Bai Huhu Cheng Chun Li Liangti Qu 《Angewandte Chemie (International ed. in English)》2020,59(34):14541-14549
Capacitive energy storage has advantages of high power density, long lifespan, and good safety, but is restricted by low energy density. Inspired by the charge storage mechanism of batteries, a spatial charge density (SCD) maximization strategy is developed to compensate this shortage by densely and neatly packing ionic charges in capacitive materials. A record high SCD (ca. 550 C cm?3) was achieved by balancing the valance and size of charge‐carrier ions and matching the ion sizes with the pore structure of electrode materials, nearly five times higher than those of conventional ones (ca. 120 C cm?3). The maximization of SCD was confirmed by Monte Carlo calculations, molecular dynamics simulations, and in situ electrochemical Raman spectroscopy. A full‐cell supercapacitor was further constructed; it delivers an ultrahigh energy density of 165 Wh L?1 at a power density of 150 WL?1 and retains 120 Wh L?1 even at 36 kW L?1, opening a pathway towards high‐energy‐density capacitive energy storage. 相似文献
997.
Hai‐Dong Xia Zhong‐Liang Li Qiang‐Shuai Gu Xiao‐Yang Dong Jia‐Heng Fang Xuan‐Yi Du Li‐Lei Wang Xin‐Yuan Liu 《Angewandte Chemie (International ed. in English)》2020,59(39):16926-16932
We describe a photoinduced copper‐catalyzed asymmetric radical decarboxylative alkynylation of bench‐stable N‐hydroxyphthalimide(NHP)‐type esters of racemic alkyl carboxylic acids with terminal alkynes, which provides a flexible platform for the construction of chiral C(sp3)?C(sp) bonds. Critical to the success of this process are not only the use of the copper catalyst as a dual photo‐ and cross‐coupling catalyst but also tuning of the NHP‐type esters to inhibit the facile homodimerization of the alkyl radical and terminal alkyne, respectively. Owing to the use of stable and easily available NHP‐type esters, the reaction features a broader substrate scope compared with reactions using the alkyl halide counterparts, covering (hetero)benzyl‐, allyl‐, and aminocarbonyl‐substituted carboxylic acid derivatives, and (hetero)aryl and alkyl as well as silyl alkynes, thus providing a vital complementary approach to the previously reported method. 相似文献
998.
Xiangyu Ma Yuyuan Bai Yongbo Song Qinzhen Li Ying Lv Hui Zhang Haizhu Yu Manzhou Zhu 《Angewandte Chemie (International ed. in English)》2020,59(39):17234-17238
Precise atomic structure of metal nanoclusters (NCs) is fundamental for elucidating the structure–property relationships and the inherent size‐evolution principles. Reported here is the largest known FCC‐based (FCC=face centered cubic) silver nanocluster, [Ag100(SC6H33,4F2)48(PPh3)8]?: the first all‐octahedral symmetric nesting Ag nanocluster with a four‐layered Ag6@Ag38@Ag48S24@Ag8S24P8 structure, consistent symmetry elements, and a unique rhombicuboctahedral morphology distinct from theoretical predictions and previously reported FCC‐based Ag clusters. DFT studies revealed extensive interlayer interactions and degenerate frontier orbitals. The FCC‐based Russian nesting doll model constitutes a new platform for the study of the size‐evolution principles of Ag NCs. 相似文献
999.
Chen Sun Ya‐Hui Guo Sha‐Sha Han Jing‐Zhao Li Kuan Jiang Lin‐Feng Dong Qi‐Long Liu Cheng‐Yang Yue Xiao‐Wu Lei 《Angewandte Chemie (International ed. in English)》2020,59(38):16465-16469
Considering the instability and low photoluminescence quantum yield (PLQY) of blue‐emitting perovskites, it is still challenging and attractive to construct single crystalline hybrid lead halides with highly stable and efficient blue light emission. Herein, by rationally introducing d10 transition metal into single lead halide as new structural building unit and optical emitting center, we prepared a bimetallic halide of [(NH4)2]CuPbBr5 with new type of three‐dimensional (3D) anionic framework. [(NH4)2]CuPbBr5 exhibits strong band‐edge blue emission (441 nm) with a high PLQY of 32 % upon excitation with UV light. Detailed photophysical studies indicate [(NH4)2]CuPbBr5 also displays broadband red light emissions derived from self‐trapped states. Furthermore, the 3D framework features high structural and optical stabilities at extreme environments during at least three years. To our best knowledge, this work represents the first 3D non‐perovskite bimetallic halide with highly efficient and stable blue light emission. 相似文献
1000.