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21.
Yang Su Xinlu Wang Minghang Zhang Huimin Guo Prof. Haizhu Sun Gang Huang Prof. Dongtao Liu Prof. Guangshan Zhu 《Angewandte Chemie (International ed. in English)》2023,62(45):e202308182
Zn-I2 batteries have attracted attention due to their low cost, safety, and environmental friendliness. However, their performance is still limited by the irreversible growth of Zn dendrites, hydrogen evolution reactions, corrosion, and shuttle effect of polyiodide. In this work, we have prepared a new porous polymer (CD-Si) by nucleophilic reaction of β-cyclodextrin with SiCl4, and CD-Si is applied to the solid polymer electrolyte (denoted PEO/PVDF/CD-Si) to solve above-mentioned problems. Through the anchoring of the CD-Si, a conductive network with dual transmission channels was successfully constructed. Due to the non-covalent anchoring effect, the ionic conductivity of the solid polymer electrolytes (SPE) can reach 1.64×10−3 S cm−1 at 25 °C. The assembled symmetrical batteries can achieve highly reversible dendrite-free galvanizing/stripping (stable cycling for 7500 h at 5 mA cm−2 and 1200 h at 20 mA cm−2). The solid-state Zn-I2 battery shows an ultra-long life of over 35,000 cycles at 2 A g−1. Molecular dynamics simulations are performed to elucidate the working mechanism of CD-Si in the polymer matrix. This work provides a novel strategy towards solid electrolytes for Zn-I2 batteries. 相似文献
22.
Dr. Junning Kou Dr. Qi Wu Dr. Dongxu Cui Dr. Yun Geng Dr. Kunhao Zhang Prof. Dr. Min Zhang Prof. Dr. Hongying Zang Prof. Dr. Xinlong Wang Prof. Dr. Zhongmin Su Prof. Dr. Chunyi Sun 《Angewandte Chemie (International ed. in English)》2023,62(47):e202312733
Chiral induction has been an important topic in chemistry, not only for its relevance in understanding the mysterious phenomenon of spontaneous symmetry breaking in nature but also due to its critical implications in medicine and the chiral industry. The induced chirality of fullerenes by host–guest interactions has been rarely reported, mainly attributed to their chiral resistance from high symmetry and challenges in their accessibility. Herein, we report two new pairs of chiral porous aromatic cages (PAC), R- PAC-2 , S- PAC-2 (with Br substituents) and R- PAC-3 , S- PAC-3 (with CH3 substituents) enantiomers. PAC-2 , rather than PAC-3 , achieves fullerene encapsulation and selective binding of C70 over C60 in fullerene carbon soot. More significantly, the occurrence of chiral induction between R- PAC-2 , S- PAC-2 and fullerenes is confirmed by single-crystal X-ray diffraction and the intense CD signal within the absorption region of fullerenes. DFT calculations reveal the contribution of electrostatic effects originating from face-to-face arene-fullerene interactions dominate C70 selectivity and elucidate the substituent effect on fullerene encapsulation. The disturbance from the differential interactions between fullerene and surrounding chiral cages on the intrinsic highly symmetric electronic structure of fullerene could be the primary reason accounting for the induced chirality of fullerene. 相似文献
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Sandwich‐Structured Graphene–Nickel Silicate–Nickel Ternary Composites as Superior Anode Materials for Lithium‐Ion Batteries 下载免费PDF全文
Renxi Jin Yang Yang Yunfeng Li Xianchun Liu Prof. Yan Xing Dr. Shuyan Song Prof. Zhan Shi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(25):9014-9017
We report the synthesis of sandwich‐structured graphene–nickel silicate–Ni ternary composites by using the solvothermal method followed by a simple in situ reduction procedure. The composites show an interesting structure with graphene sandwiched between two layers of well‐dispersed Ni nanoparticles (NPs) anchored on ultrathin nickel silicate nanosheets. These ternary composites exhibit enhanced performance as anode materials owing to the synergistic effect between the graphene matrix and electrochemically inert Ni nanoparticles, an effect that holds promise for the design and fabrication of other advanced electrode materials. 相似文献
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将无机化学中的脱水缩合反应进行分类:发生在无机含氧酸之间的脱水缩合反应;发生在无机含氧酸酸式盐之间的脱水缩合反应和酸化含氧酸盐溶液而发生的脱水缩合反应。介绍了缩合反应及缩合反应产物的应用。 相似文献
25.
A facile, effective, and environmentally friendly method has been adopted for the first time to prepare tiny Co3O4 nanocrystals embedded carbon matrices without using surfactants, harmful organic reagents or extreme conditions. Structural characterizations reveal that the size-controlled Co3O4 nanocrystals are uniformly dispersed on carbon matrices. Electrochemical measurements reveal that Co3O4-ordered mesoporous carbon (OMC) can more efficiently catalyze glucose oxidation and acquire better detection parameters compared with those for the Co3O4-macroporous carbon, Co3O4-reduced graphene oxide, and free Co3O4 nanoparticles (NPs) (such as: the large sensitivity (2597.5 μA cm−2 mM−1 between 0 and 0.8 mM and 955.9 μA cm−2 mM−1 between 0.9 and 7.0 mM), fast response time, wide linear range, good stability, and surpassingly selective capability to electroactive molecules or Cl−). Such excellent performances are attributed to the synergistic effect of the following three factors: (1) the high catalytic sites provided by the uniformly dispersed and size-controlled Co3O4 nanocrystals embedded on OMC; (2) the excellent reactant transport efficiency caused by the abundant mesoporous structures of OMC matrix: (3) the improved electron transport in high electron transfer rate (confinement of the Co3O4 NPs in nanoscale spaces ensured intimate contact between Co3O4 nanocrystals and the conducting OMC matrix). The superior catalytic activity and selectivity make Co3O4-OMC very promising for application in direct detection of glucose. 相似文献
26.
Feng‐Yang Bai Xiao‐Le Zhu Zi‐Man Jia Xu Wang Yan‐Qiu Sun Prof. Rong‐Shun Wang Prof. Xiu‐Mei Pan 《Chemphyschem》2015,16(8):1768-1776
The mechanism and kinetics of the reactions of CF3COOCH2CH3, CF2HCOOCH3, and CF3COOCH3 with Cl and OH radicals are studied using the B3LYP, MP2, BHandHLYP, and M06‐2X methods with the 6‐311G(d,p) basis set. The study is further refined by using the CCSD(T) and QCISD(T)/6‐311++G(d,p) methods. Seven hydrogen‐abstraction channels are found. All the rate constants, computed by a dual‐level direct method with a small‐curvature tunneling correction, are in good agreement with the experimental data. The tunneling effect is found to be important for the calculated rate constants in the low‐temperature range. For the reaction of CF3COOCH2CH3+Cl, H‐abstraction from the CH2 group is found to be the dominant reaction channel. The standard enthalpies of formation for the species are also calculated. The Arrhenius expressions are fitted within 200–1000 K as kT(1)=8.4×10?20T 2.63exp(381.28/T), kT(2)=2.95×10?21T 3.13exp(?103.21/T), kT(3)=1.25×10?23T 3.37exp(791.98/T), and kT(4)=4.53×10?22T 3.07exp(465.00/T). 相似文献
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K-ion batteries (KIBs) attract considerable attention due to the abundance of K, high-working voltages, and chemical similarity with Li, enabling the utilization of mature Li-ion technology. However, shortage of high-performance anode materials is a critical obstacle for the development of KIBs. Through first-principles swarm-intelligence structural search, we identify a potential anode material, the C6S monolayer, which provides not only a remarkably high specific capacity of 1546 mAh/g but also a low diffusion barrier of 0.11 eV and a low open-circuit voltage of 0.21 V. Inherent metallicity originates from delocalized π electrons. 相似文献