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1.
Hailong Yue Congying Ren Guangming Wang Prof. Guihua Li Prof. Rencheng Jin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(46):10575-10584
Transition metal oxides, as one of the most promising anode materials for lithium-ion batteries, often suffer from poor electronic conductivity and serious structural collapse. In this work, oxygen-vacancy-abundant CoFe2O4 and NiFe2O4 deposited on N-doped carbon nanosheets are designed and fabricated through a calcination procedure and a solvothermal strategy using Zn-hexamine coordination frameworks as precursors. The as-prepared NC@CoFe2O4 and NC@NiFe2O4 hybrids display improved cycle performances and rate capacities compared with CoFe2O4, NiFe2O4, and Fe2O3. The enhanced lithium storage performances of NC@CoFe2O4 and NC@NiFe2O4 are attributed to the oxygen vacancies and conductive N-doped carbon nanosheets, which increase the electronic conductivity and electrochemical reaction kinetics. The synthetic process in this work provides a new perspective for designing other high-performance transition metal oxide anodes. 相似文献
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Summary: A novel kind of dendronized porphyrin polymers was synthesized by Sonogashira coupling of diethynyl‐functionalized porphyrin monomers and diiodo‐functionalized macromonomers bearing Fréchet‐type dendrons. The encapsulation of red‐light‐emitting porphyrin‐containing conjugated backbones into dendronized polymers can not only reduce the aggregation of polymer backbones and the self‐quenching of their fluorescence but also endow the porphyrin polymers with good solubility. We also report the optical and electrochemical properties of the porphyrin‐containing dendronized polymers.
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合成了两种不同类型(2+2型、A4型)含二氢噻唑基团的锌卟啉与Mn(Ⅱ)的配位聚合物(CPsx,x=1,2)。两种配位聚合物与锚定卟啉(ZnPA)通过金属-配体轴向配位自组装成染料敏化太阳能电池。通过电镜表征了其在TiO2上的自组装结构。光伏性能测试表明,聚合物自组装体与单体相比具有较优的光电转换效率,特别是A4型结构(CPs2)具有较高的短路电流和转换效率。 相似文献
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Jinfu Zhao Dr. Wenxian Wei Dr. Na Xu Dr. Xiaotong Wang Prof. Limin Chang Dr. Li Wang Luan Fang Dr. Zaiyuan Le Dr. Ping Nie 《Chemphyschem》2022,23(9):e202200233
The front cover artwork is provided by Dr. Ping Nie and Prof. Limin Chang at Jilin Normal University. The image shows one-dimensional silicon–nitrogen-doped carbon nanotube composite fabricated through a dealloying process. The nanotube engineered silicon coupled with conductive carbon coating synergistically boosts the electrochemical performance. Read the full text of the Research Article at 10.1002/cphc.202100832 . 相似文献
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Dr. Joseph K.‐H. Hui Hiroyuki Kishida Keita Ishiba Kenta Takemasu Dr. Masa‐aki Morikawa Prof. Dr. Nobuo Kimizuka 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(40):14213-14218
A new class of ferroelectric coordination‐based polymers has been developed by the self‐assembly of lipophilic zinc porphyrin ( ZnP ) and ditopic bridging ligands. The ligands contain dipolar benzothiadiazole or fluorobenzene units, which are axially coordinated to ZnP with the dipole moments oriented perpendicular to the coordination axes. The coordination‐based polymers show ferroelectric characteristics in the liquid crystalline state, as revealed by distinctive hysteresis in the polarization–electric field (P–E) loops and inversion current peaks in current–voltage (I–V) loops. The observed ferroelectric properties are explainable by flip–flop rotation of the dipolar axle ligands induced by the applied electric field, as demonstrated by the positive‐up–negative‐down (PUND) measurements. The present system provides a new operating principle in supramolecular ferroelectrics. 相似文献
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Mihaela-Ramona Buga Adnana Alina Spinu-Zaulet Cosmin Giorgian Ungureanu Raul-Augustin Mitran Eugeniu Vasile Mihaela Florea Florentina Neatu 《Molecules (Basel, Switzerland)》2021,26(15)
Porous silica-based materials are a promising alternative to graphite anodes for Li-ion batteries due to their high theoretical capacity, low discharge potential similar to pure silicon, superior cycling stability compared to silicon, abundance, and environmental friendliness. However, several challenges prevent the practical application of silica anodes, such as low coulombic efficiency and irreversible capacity losses during cycling. The main strategy to tackle the challenges of silica as an anode material has been developed to prepare carbon-coated SiO2 composites by carbonization in argon atmosphere. A facile and eco-friendly method of preparing carbon-coated SiO2 composites using sucrose is reported herein. The carbon-coated SiO2 composites were characterized using X-ray diffraction, X-ray photoelectron spectroscopy, thermogravimetry, transmission and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy, cyclic voltammetry, and charge–discharge cycling. A C/SiO2-0.085 M calendered electrode displays the best cycling stability, capacity of 714.3 mAh·g−1, and coulombic efficiency as well as the lowest charge transfer resistance over 200 cycles without electrode degradation. The electrochemical performance improvement could be attributed to the positive effect of the carbon thin layer that can effectively diminish interfacial impedance. 相似文献
7.
Jin Wang Dr. Gang Huang Kai Chen Prof. Xin-Bo Zhang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(24):9468-9473
The limited triple-phase boundaries (TPBs) in solid-state cathodes (SSCs) and high resistance imposed by solid electrolytes (SEs) make the achievement of high-performance all-solid-state lithium-oxygen (ASS Li-O2) batteries a challenge. Herein, an adjustable-porosity plastic crystal electrolyte (PCE) has been fabricated by employing a thermally induced phase separation (TIPS) technique to overcome the above tricky issues. The SSC produced through the in-situ introduction of the porous PCE on the surface of the active material, facilitates the simultaneous transfer of Li+/e−, as well as ensures fast flow of O2, forming continuous and abundant TPBs. The high Li+ conductivity, softness, and adhesion of the dense PCE significantly reduce the battery resistance to 115 Ω. As a result, the ASS Li-O2 battery based on this adjustable-porosity PCE exhibits superior performances with high specific capacity (5963 mAh g−1), good rate capability, and stable cycling life up to 130 cycles at 32 °C. This novel design and exciting results could open a new avenue for ASS Li-O2 batteries. 相似文献
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Qinghua Gong Haiqing Wang Wenhua Song Bin Sun Pei Cao Shaonan Gu Xuefeng Sun Prof. Guowei Zhou 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(8):2654-2661
This work reports the preparation of unique hierarchical yolk/double-shelled SiOx@TiO2@C nanospheres with different voids by a facile sol-gel method combined with carbon coating. In the preparation process, SiOx nanosphere is used as a hard template. Etch time of SiOx yolk affects the morphology and electrochemical performance of SiOx@TiO2@C. With the increase in etch time, the yolk/double-shelled SiOx@TiO2@C with 15 and 30 nm voids and the TiO2@C hollow nanospheres are obtained. The yolk/double-shelled SiOx@TiO2@C nanospheres exhibit remarkable lithium-ion battery performance as anodes, including high lithium storage capacity, outstanding rate capability, good reversibility, and stable long-term cycle life. The unique structure can accommodate the large volume change of the SiOx yolk, provide a unique buffering space for the discharge/charge processes, improve the structural stability of the electrode material during repeated Li+ intercalation/deintercalation processes, and enhance the cycling stability. The SiOx@TiO2@C with 30 nm void space exhibits a high discharge specific capacity of ≈1195.4 mA h g−1 at the current density of 0.1 A g−1 after 300 cycles and ≈701.1 mA h g−1 at 1 A g−1 for over 800 cycles. These results suggest that the proposed particle architecture is promising and may have potential applications in improving various high performance anode materials. 相似文献
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Synthesis of Highly Uniform Molybdenum–Glycerate Spheres and Their Conversion into Hierarchical MoS2 Hollow Nanospheres for Lithium‐Ion Batteries 下载免费PDF全文
Dr. Yawen Wang Dr. Le Yu Prof. Xiong Wen Lou 《Angewandte Chemie (International ed. in English)》2016,55(26):7423-7426
Highly uniform Mo–glycerate solid spheres are synthesized for the first time through a solvothermal process. The size of these Mo–glycerate spheres can be easily controlled in the range of 400–1000 nm by varying the water content in the mixed solvent. As a precursor, these Mo–glycerate solid spheres can be converted into hierarchical MoS2 hollow nanospheres through a subsequent sulfidation reaction. Owing to the unique ultrathin subunits and hollow interior, the as‐prepared MoS2 hollow nanospheres exhibit appealing performance as the anode material for lithium‐ion batteries. Impressively, these hierarchical structures deliver a high capacity of about 1100 mAh g?1 at 0.5 A g?1 with good rate retention and long cycle life. 相似文献
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Dr. Chao Hu Dr. Juan Yang Prof. Chang Yu Shaofeng Li Ye Mu Silin Bai Man Wang Sucen Liang Prof. Jieshan Qiu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(21):5527-5533
Metal oxide coupling with carbon materials holds great promise for lithium storage. Herein, multilevel coupled cobalt oxide–graphene (CoO/CO3O4–G) hybrids were fabricated by in situ assembly of Co hydroxide precursors and a calcination process. The oxygen-containing functional groups on the graphene surface act as bridging sites and tend to bond with Co2+ ions, effectively modifying the morphology and structure of the Co species. The as-obtained CoO/CO3O4–G hybrids are composed of unique CoO/CO3O4 porous nanoparticles uniformly anchored on graphene sheets, as confirmed by a series of characterization analyses. Benefiting from these structural characteristics, the CoO/CO3O4–G hybrids used as an anode can deliver a high capacity of about 1080 mA h g−1 reversibly at 0.1 Ag−1 in the voltage range between 3.0 and 0.01 V, which is remarkably superior to that of the CoO hexagonal sheets in the absence of graphene. The high reversible capacity of the CoO/CO3O4–G hybrids is retained at elevated current densities, for example, a capacity of approximately 455 mA h g−1 can be achieved at a current rate as high as 4 A g−1, indicative of its potential for high-performance lithium-ion batteries. 相似文献
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Jiajia Ru Ting He Binjie Chen Yutong Feng Lianhai Zu Prof. Zhijun Wang Prof. Qiaobao Zhang Tianzi Hao Ruijin Meng Prof. Renchao Che Prof. Chi Zhang Prof. Jinhu Yang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(34):14729-14735
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
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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
16.
Anthony K. Burrell Ben M. Jones Simon B. Hall David L. Officer David C. W. Reid Kirstie Y. Wild 《Journal of inclusion phenomena and macrocyclic chemistry》1999,35(1-2):185-190
The self-assembly of porphyrin arrays containing three, seven or eleven porphyrins results from the interaction of the bis-pyridyl porphyrin 1 with the zinc porphyrins 2, 3, or 4, respectively. 相似文献
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Inside Back Cover: Synthesis of Highly Uniform Molybdenum–Glycerate Spheres and Their Conversion into Hierarchical MoS2 Hollow Nanospheres for Lithium‐Ion Batteries (Angew. Chem. Int. Ed. 26/2016) 下载免费PDF全文
Dr. Yawen Wang Dr. Le Yu Prof. Xiong Wen Lou 《Angewandte Chemie (International ed. in English)》2016,55(26):7549-7549
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为提高柔性锂离子电池安全性和循环稳定性能,本实验以自由基聚合结合冷冻干燥得到的聚丙烯酰胺膜为电解质载体,引入21 mol·kg-1 LiTFSI 高浓度电解液,得到“water-in-salt”聚合物电解质。通过聚合物膜的形貌和孔道结构表征,红外光谱分析,离子电导率及电化学稳定窗口测试等对其基本物化特性进行了研究。冷冻干燥得到的聚丙烯酰胺膜内部具有大量微孔结构,有利于电解液的载入。将该吸附了电解液的聚合物电解质膜与锰酸锂(LiMn2O4)正极和磷酸钛锂(LiTi2(PO4)3)负极组装全电池进行充放电性能测试。结果表明,制得的柔性聚合物电解质具有良好的拉伸性能,高离子电导率(20°C,4.34 mS·cm-1)和宽电化学稳定窗口(3.12 V)。以“water-in-salt”聚合物电解质为隔膜组装的LiMn2O4||LiTi2(PO4)3 全电池表现出优异的倍率性能和长循环稳定性。 相似文献
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合成了2种新型锌卟啉并与金属Mn构建配位聚合物(CPsx,x=1,2)。2种配位聚合物与锚定卟啉(ZnPA)通过金属-配体轴向配位自组装染料敏化太阳能电池(DSSC)。测试结果表明自组装电池具有较好的光电转换效率,特别是基于CPs2的装置具有较高的短路电流和转换效率。我们还对其光学、电化学及光电性能进行了研究,并通过透射电镜(TEM)对自组装体有效敏化在TiO_2电极上进行验证。 相似文献