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121.
One‐Pot Synthesis of Pomegranate‐Structured Fe3O4/Carbon Nanospheres‐Doped Graphene Aerogel for High‐Rate Lithium Ion Batteries 下载免费PDF全文
Dr. Dafang He Lixian Li Fengjuan Bai Chenyang Zha Prof. Liming Shen Prof. Harold H. Kung Prof. Ningzhong Bao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(13):4454-4459
A unique hierarchically nanostructured composite of iron oxide/carbon (Fe3O4/C) nanospheres‐doped three‐dimensional (3D) graphene aerogel has been fabricated by a one‐pot hydrothermal strategy. In this novel nanostructured composite aerogel, uniform Fe3O4 nanocrystals (5–10 nm) are individually embedded in carbon nanospheres (ca. 50 nm) forming a pomegranate‐like structure. The carbon matrix suppresses the aggregation of Fe3O4 nanocrystals, avoids direct exposure of the encapsulated Fe3O4 to the electrolyte, and buffers the volume expansion. Meanwhile, the interconnected 3D graphene aerogel further serves to reinforce the structure of the Fe3O4/C nanospheres and enhances the electrical conductivity of the overall electrode. Therefore, the carbon matrix and the interconnected graphene network entrap the Fe3O4 nanocrystals such that their electrochemical function is retained even after fracture. This novel hierarchical aerogel structure delivers a long‐term stability of 634 mA h g?1 over 1000 cycles at a high current density of 6 A g?1 (7 C), and an excellent rate capability of 413 mA h g?1 at 10 A g?1 (11 C), thus exhibiting great potential as an anode composite structure for durable high‐rate lithium‐ion batteries. 相似文献
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《中国化学》2018,36(2):157-161
The three‐dimensional nanoflower‐like β‐In2S3 composited with carbon nanotubes (CNTs) has been synthesized by a single mode microwave‐assisted hydrothermal technique. The In2S3 and CNTs nanocomposites (In2S3@CNTs) were investigated as the anode materials of lithium batteries (LIBs) and the electromagnetic wave absorption materials. For LIBs applications, the In2S3@CNTs nanocomposite exhibited excellent cycling stability with a high reversible charge capacity of 575 mA⋅h⋅g–1 after 300 cycles at 0.5 A⋅g–1. In addition, the In2S3@CNTs used as electromagnetic wave absorber displayed a maximum reflection loss of –42.75 dB at 11.96 GHz with a thickness of 1.55 mm. 相似文献
125.
A Supramolecular Chiral Auxiliary Approach: “Remote Control” of Stereochemistry at a Hierarchically Assembled Dimeric Helicate 下载免费PDF全文
David Van Craen Prof. Dr. Markus Albrecht Prof. Dr. Gerhard Raabe Fangfang Pan Prof. Dr. Kari Rissanen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(10):3255-3258
Dimeric hierarchically‐assembled titanium(IV) helicates are in solvent‐dependent equilibrium with the corresponding monomers. Statistically formed mixtures of such complexes bearing chiral stereocontrolling ligands and achiral diene‐substituted ligands show high diastereoselectivity and reasonable enantioselectivity in the Diels–Alder reaction with maleimides if the reaction proceeds with the dimer but not with the monomer. Thus, solvent dependent switching between the monomer and dimer enables on/off switching of the enantioselectivity. 相似文献
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将CR2032型锂离子电池的制作及电化学性能测试实验设计为大学化学本科生的综合实验并将其应用于本科教学中,建立起基于锂离子电池用正极材料的合成、表征、电极制备及电池组装和性能测试的综合性开放实验。实验以无机材料制备为实验基础,以电化学原理为理论基础,通过文献查阅、确立合成路线、材料制备及表征、锂离子电池制作与测试等多项综合实验内容,使学生了解目前常见的正极材料种类、合成方法、电池的基本结构以及电池性能的测试方法。在教学过程中以学生主动探索为主体,培养学生的科学探究素养,锻炼学生查阅文献、自主设计实验和合作开发的能力。 相似文献
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Ray L. Frost Yunfei Xi Ricardo Scholz Andrés López Fernanda M. Belotti Mário L. S. C. Chaves 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):1526-1534
Abstract The metal lithium is very important in industry, including lithium batteries. An important source of lithium besides continental brines is granitic pegmatites as in Australia. Lithiophilite is a lithium and manganese phosphate with chemical formula LiMnPO4 and forms a solid solution with triphylite, its Fe analog, and belongs to the triphylite group that includes karenwebberite, natrophilite, and sicklerite. The mineral lithiophilite was characterized by chemical analysis and spectroscopic techniques. The chemical is: Li1.01(Mn0.60, Fe0.41, Mg0.01, Ca0.01)(PO4)0.99 and corresponds to an intermediate member of the triphylite-lithiophilite series, with predominance of the lithiophilite member. The mineral lithiophilite is readily characterized by Raman and infrared spectroscopy. 相似文献
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