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31.
Germanium Quantum Dots Embedded in N‐Doping Graphene Matrix with Sponge‐Like Architecture for Enhanced Performance in Lithium‐Ion Batteries
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Jinwen Qin Xia Wang Prof. Dr. Minhua Cao Changwen Hu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(31):9675-9682
Germanium quantum dots embedded in a nitrogen‐doped graphene matrix with a sponge‐like architecture (Ge/GN sponge) are prepared through a simple and scalable synthetic method, involving freeze drying to obtain the Ge(OH)4/graphene oxide (GO) precursor and subsequent heat reduction treatment. Upon application as an anode for the lithium‐ion battery (LIB), the Ge/GN sponge exhibits a high discharge capacity compared with previously reported N‐doped graphene. The electrode with the as‐synthesized Ge/GN sponge can deliver a capacity of 1258 mAh g?1 even after 50 charge/discharge cycles. This improved electrochemical performance can be attributed to the pore memory effect and highly conductive N‐doping GN matrix from the unique sponge‐like structure. 相似文献
32.
Platinum Complexes Containing Pyramidalized Germanium and Tin Dihalide Ligands Bound through σ,σ ME Multiple Bonds
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Florian Hupp Dr. Mengtao Ma Franziska Kroll Dr. J. Oscar C. Jimenez‐Halla Dr. Rian D. Dewhurst Dr. Krzysztof Radacki Dr. Andreas Stasch Prof. Dr. Cameron Jones Prof. Dr. Holger Braunschweig 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(51):16888-16898
We present the isolation of the first mononuclear dihalogermylene, and mono‐ and dinuclear stannylene complexes of transition metals. These exhibit exceptionally pyramidalized Group 14 centers. Additionally, removal of the halide substituents from the Ge/Sn atom was successfully performed in two ways, halide abstraction and reduction, leading to a variety of unusual structural motifs. 相似文献
33.
Can Low‐Valent Germanium Chemistry Be Practiced Under Ambient Conditions? A Tale of a Water‐Stable Yet Reactive Germylene Monochloride Complex
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Chandan Kumar Jha Surendar Karwasara Dr. Selvarajan Nagendran 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(33):10240-10244
A germylene monochloride complex ((DPM)GeCl, 1 ) that is water stable was isolated for the first time. Interestingly, it reacts with cesium fluoride under ambient conditions (non‐inert atmosphere and water‐containing solvent) to afford water stable germylene monofluoride complex ((DPM)GeF, 2 ). Due to the usage of DPM (dipyrrinate) ligand, germylene monohalides 1 and 2 show fluorescence in the visible region at 555 and 538 nm, respectively. Compounds 1 and 2 are the first fluorescent germylene complexes and were characterized by multinuclear NMR spectroscopy. The structure of compound 1 was also proved by single crystal X‐ray diffraction studies. 相似文献
34.
Jonathan W. Dube Cameron M. E. Graham Prof. Charles L. B. Macdonald Dr. Zachary D. Brown Prof. Philip P. Power Prof. Paul J. Ragogna 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(22):6739-6744
Two unique systems based on low‐coordinate main group elements that activate P4 are shown to quantitatively release the phosphorus cage upon short exposure to UV light. This reactivity marks the first reversible reactivity of P4, and the germanium system can be cycled 5 times without appreciable loss in activity. Theoretical calculations reveal that the LUMO is antibonding with respect to the main group element–phosphorus bonds and bonding with respect to reforming the P4 tetrahedron, providing a rationale for this unprecedented activity, and suggesting that the process is tunable based on the substituents. 相似文献
35.
建立电感耦合等离子体质谱法同时测定地质样品中镉、锗、钴含量的分析方法。样品用氢氟酸-硝酸混合溶液加热溶解,然后加热浓缩驱酸,再用硝酸溶液(1+1)复溶提取,在选定的仪器工作条件下进行测定。镉、锗、钴的含量分别在0.00~0.10,0.00~5.00,0.00~50.00 μg/g范围内与质谱峰强度呈良好的线性关系,相关系数均大于0.999,方法检出限分别为0.01,0.02,0.02 μg/g。用该方法对国家一级标准物质进行测定,测定值的相对误差均小于10%,测定结果的相对标准偏差为0.79%~8.45%(n=12)。该方法样品处理过程简便,检测效率高,适用于批量地质样品中镉、锗、钴的测定。 相似文献
36.
Zhenghai Yang Chao He Srinivas Doddipatla Vladislav S. Krasnoukhov Prof. Valeriy N. Azyazov Prof. Alexander M. Mebel Prof. Ralf I. Kaiser 《Chemphyschem》2020,21(17):1898-1904
The methylgermylene species (HGeCH3; X1A′) has been synthesized via the bimolecular gas phase reaction of ground state methylidyne radicals (CH) with germane (GeH4) under single collision conditions in crossed molecular beams experiments. Augmented by electronic structure calculations, this elementary reaction was found to proceed through barrierless insertion of the methylidyne radical in one of the four germanium-hydrogen bonds on the doublet potential energy surface yielding the germylmethyl (CH2GeH3; X2A′) collision complex. This insertion is followed by a hydrogen shift from germanium to carbon and unimolecular decomposition of the methylgermyl (GeH2CH3; X2A′) intermediate by atomic hydrogen elimination leading to singlet methylgermylene (HGeCH3; X1A′). Our investigation provides a glimpse at the largely unknown reaction dynamics and isomerization processes of the carbon-germanium system, which are quite distinct from those of the isovalent carbon system thus providing insights into the intriguing chemical bonding of organo germanium species on the most fundamental, microscopic level. 相似文献
37.
38.
A new complex K0.5[K(18-crown-6)]1.5Ge9·1.5en(1) which contains unprecedented "up" and "down" chain arrangement of unit [-(Ge-9-K-Ge9)3-] has been prepared by the reaction of K4Ge9 with HgS in ethylenediamine(en) in the presence of 18-crown-6(1,4,7,10,13,16-hexaoxacyclooctadecane), and characterized by X-ray structure analysis. The color of the title crystals(black), which is darker than that of the reported three compounds with chains of germanium clusters, may result from the naked K+ and their interactions with the chain. And the structure differences between 1 and the reported three compounds with chains of germanium have also been discussed. 相似文献
39.
Lead tellurite is study to show that solid electrolyte GeSe-GeI2, which has the optimum composition and contains 5 mol % of GeI2, can in principle be used for electrochemical doping of semiconducting materials with germanium by the coulometric titration method. Some parameters of the coulometric titration are considered. The doping efficiency is monitored by determining variations in the concentration of charge carriers using the Hall method and by measuring the EMF of corresponding galvanic cells. 相似文献
40.
建立了测定煤矸石中微量锗和镓的电感耦合等离子体质谱法。煤矸石试样经高温灰化,用硝酸-氢氟酸-高氯酸-磷酸分解,以电感耦合等离子体质谱法测定其中的锗和镓。通过在线三通加入内标元素铑,消除非质谱干扰;通过选择干扰元素的异质同位素进行定量测定,采用数学公式在线校正,消除质谱干扰。与分光光度法进行比对,锗、镓测定结果的相对偏差为-0.63%~0.28%。克服了常规化学分析方法步骤繁琐、耗时长、工作量大的不足。该法测定结果的相对标准偏差小于3%(n=6),加标回收率为97.4%~102.5%。该方法具有检出限低、快速、简便、线性范围宽、多元素同时测定等优点,分析误差满足化学分析法的要求,可用于煤矸石中锗和镓的测定。 相似文献