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Ningbo, China

Ningbo University of Technology is a comprehensive provincial university located in Ningbo, Zhejiang province of the People's Republic of China. Wikipedia.


Jiang Z.,Ningbo University of Technology | Jiang Z.-J.,University of California at Merced
Journal of Alloys and Compounds | Year: 2012

Nanosized LiFePO 4/C core/shell nanocomposites with different carbon shell thicknesses have been synthesized by a simple two-step procedure. The effects of carbon shell thickness on the electrochemical performance of these LiFePO 4/C core/shell nanocomposites have been investigated. It shows that the LiFePO 4/C core/shell nanocomposites with low carbon shell thicknesses exhibit poor electrochemical performance when used in lithium ion batteries, presumably due to presence of structural disorders and defects in the particle surface layers. An increase of carbon shell thickness can remove the structural disorders and defects. The LiFePO 4/C core/shell nanocomposites with higher carbon shell thicknesses therefore exhibit significantly improved electrochemical performance. However, further increase of carbon shell thickness would lead to a decrease in the charge/discharge capacity of the LiFePO 4/C core/shell nanocomposites, although these LiFePO 4/C core/shell nanocomposites still exhibit high cycling stability. That is because excess carbon shell coating would hinder the penetration of the electrolyte solution into the carbon layers and the inward/outward diffusion of Li + ions through the carbon layers, which decreases the charge/discharge capacity of the LiFePO 4/C core/shell nanocomposites. © 2012 Elsevier B.V. All rights reserved. Source


Jiang Z.-J.,South China University of Technology | Jiang Z.,Ningbo University of Technology
ACS Applied Materials and Interfaces | Year: 2014

Nitrogen-doped holey graphene hollow microspheres (NHGHSs), synthesized through a template sacrificing method, were utilized as an anode material for lithium ion batteries (LIBs). Because of their specific microspherical hollow structure comprising nitrogen-doped holey graphene (NHG), the NHGHSs can exhibit reversible capacities of ∼1563 mAh g-1 at a low rate of 0.5 C and ∼254 mAh g-1 at a high rate of 20 C, which are significantly higher than the discharge capacity of the pristine graphene and other graphene-based carbonaceous materials. These, along with their good cycling stability, clearly demonstrate the great potential of using the NHGHSs as the anode material for LIBs of both high energy and power densities. We believe that the high specific surface area, holey structure of nitrogen-doped graphene, specific microspherical hollow structure, and increased interlayer spacing between the NHG nanosheets in their hollow walls are the main origins of their high electrochemical performance. © 2014 American Chemical Society. Source


Reaction of [(μ-SCH2)2NCH2CO 2Me]Fe2(CO)6 with 4-PyN(PPh2) 2 (Py = C5H4N) in the presence of the decarbonylating agent Me3NO·2H2O afforded unexpected complexes [(μ-SCH2)2NCH2CO 2Me]Fe2(CO)5(Ph2PNHPy-4) (1) and [(μ-SCH2)2NCH2CO2Me]Fe 2(CO)5[Ph2PP(O)Ph2] (2) in 40% and 14% yields, respectively. The new complexes 1 and 2 have been characterized by elemental analysis, IR and 1H (31P, 13C) NMR spectroscopic techniques. In addition, their structures were determined by single-crystal X-ray diffraction analysis, indicating that the monophosphine ligands in complexes 1 and 2 both reside in an axial position of the square-pyramidal coordination sphere of the Fe atoms. © 2011 Elsevier B.V. All rights reserved. Source


Liu X.-F.,Ningbo University of Technology
Journal of Organometallic Chemistry | Year: 2014

A series of diiron dithiolate complexes bearing phosphine or isocyanide ligands, as the active site models of [FeFe]H2ases, has been prepared by carbonyl substitution and structurally characterized. While complexes [(μ-EDT)Fe2(CO)5L1] (EDT = SCH 2CH2S, L1 = PPh3, 3; Ph 2PCH2PPh2, 4; tBuNC, 5) were prepared by reactions of (μ-EDT)Fe2(CO)6 (1) with PPh3, Ph2PCH2PPh2 (dppm), or tBuNC in the presence of Me3NO·2H2O in MeCN in 52-82% yields, complex (μ-EDT)Fe2(CO)4( tBuNC)2 (6) was produced by reaction of 1 with 2 equivalents of tBuNC in CH2Cl2 in 42% yield. Treatment of 1 or (μ-PDT)Fe2(CO)6 (PDT = SCH 2CH2CH2S) (2) with Me3NO· 2H2O followed by addition of 4-PyN(PPh2)2 (Py = C5H4N) gave unexpected products (μ-EDT)Fe 2(CO)5[Ph2PP(O)Ph2] (7), (μ-EDT)Fe2(CO)5(Ph2PNHPy-4) (8), (μ-PDT)Fe2(CO)5[Ph2PP(O)Ph2] (9), and (μ-PDT)Fe2(CO)5(Ph2PNHPy-4) (10) in 20-38% yields, respectively. In addition, the asymmetrically disubstituted complex (μ-EDT)Fe2(CO)4(Ph2PCH 2CH2PPh2) (11) was obtained by reaction of 1 with Ph2PCH2CH2PPh2 (dppe) in refluxing xylene in 31% yield, whereas reaction of 2 with 1,1′- bis(diphenylphosphino)ferrocene (dppf) in refluxing xylene afforded the symmetrically disubstituted complex (μ-PDT)Fe2(CO) 4[(η5-Ph2PC5H4) 2Fe] (12) in 28% yield. The complexes 3-9, 11, and 12 were characterized by elemental analysis, IR, and NMR spectroscopy, as well as for 3-7, 9, 11, and 12 by X-ray crystallography. © 2013 Elsevier B.V. All rights reserved. Source


Five new diacetylenic tetracobalt carbonyl complexes 2-6 with monophosphine or diphosphines have been prepared from the parent complex (μ-HCCCH 2CH2CH2CH2CCH-μ)[Co 2(CO)6]2 (1), and their structures were fully characterized. Reaction of 1 with PPh3 in the presence of Me 3NO·2H2O afforded (μ-HCCCH2CH 2CH2CH2CCH-μ)[Co2(CO) 5(PPh3)]2 (2) in 59% yield. Similarly, reaction of 1 with dppe (Ph2PCH2CH2PPh2) in the presence of Me3NO·2H2O gave (μ-HCCCH 2CH2CH2CH2CCH-μ)[Co 2(CO)5]2(dppe) (3) and (μ-HCCCH 2CH2CH2CH2CCH-μ)[Co 2(CO)6][Co2(CO)4(dppe)] (4), with a bridging diphosphine ligand, in 20% and 16% yields, respectively, whereas (μ-HCCCH2CH2CH2CH2CCH-μ) [Co2(CO)5]2(dppp) (dppp = Ph 2PCH2CH2CH2PPh2) (5) and (μ-HCCCH2CH2CH2CH2CCH-μ) [Co2(CO)5]2(dppb) (dppb = Ph 2PCH2CH2CH2CH2PPh 2) (6) were prepared by the reactions of 1 with dppp or dppb in the presence of Me3NO·2H2O in 29% and 36% yields, respectively. The new complexes 2-6 were characterized by elemental analysis, spectroscopy and, for 1-3 and 6, by X-ray crystallography. It is interesting to note that the X-ray crystal structures of 3 and 6 contain 12 and 14 atom macrocycles, respectively. © 2014 Elsevier Ltd. All rights reserved. Source

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