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71.
We synthesized Cu3.8Ni/CoO and Cu3.8Ni/MnO nanoparticles via an easy and scalable solution synthesis.The synthesized Cu3.8Ni/CoO and Cu3.8Ni/MnO nanoparticles were annealed to remove the organic surfactants without phase transitions or side reactions.Electrons can be transferred via metallic Cu3.8Ni,which will not react with lithium ions.The heterogeneous structures of Cu3.8Ni/CoO and Cu3.8Ni/MnO nanopartides could enhance the lithium ion mobility and improve the life cycle,and these materials are therefore promising candidates as highpower-density and high-energy-density anode materials for lithium-ion batteries in diverse applications,such as electrical vehicles. 相似文献
72.
Synthesis of Uniquely Structured Yolk–Shell Metal Oxide Microspheres Filled with Nitrogen‐Doped Graphitic Carbon with Excellent Li–Ion Storage Performance 下载免费PDF全文
Novel structured composite microspheres of metal oxide and nitrogen‐doped graphitic carbon (NGC) have been developed as efficient anode materials for lithium‐ion batteries. A new strategy is first applied to a one‐pot preparation of composite (FeOx‐NGC/Y) microspheres via spray pyrolysis. The FeOx‐NGC/Y composite microspheres have a yolk–shell structure based on the iron oxide material. The void space of the yolk–shell microsphere is filled with NGC. Dicyandiamide additive plays a key role in the formation of the FeOx‐NGC/Y composite microspheres by inducing Ostwald ripening to form a yolk–shell structure based on the iron oxide material. The FeOx‐NGC/Y composite microspheres with the mixed crystal structure of rock salt FeO and spinel Fe3O4 phases show highly superior lithium‐ion storage performances compared to the dense‐structured FeOx microspheres with and without carbon material. The discharge capacities of the FeOx‐NGC/Y microspheres for the 1st and 1000th cycle at 1 A g?1 are 1423 and 1071 mAh g?1, respectively. The microspheres have a reversible discharge capacity of 598 mAh g?1 at an extremely high current density of 10 A g?1. Furthermore, the strategy described in this study is generally applied to multicomponent metal oxide–carbon composite microspheres with yolk–shell structures based on metal oxide materials. 相似文献
73.
74.
Dong‐Hui Yang Lingjun Kong Ming Zhong Jian Zhu Xian‐He Bu 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(3)
The development of cost‐effective and flexible electrodes is demanding in the field of energy storage. Herein, flexible FexOy/nitrogen‐doped carbon films (FexOy/NC‐MOG) are prepared by facile electrospinning of Fe‐based metal–organic gels (MOGs) followed by high‐temperature carbonization. This approach allows the even mixing of fragile coordination polymers with polyacrylonitrile into flexible films while reserving the structural characteristics of coordination polymers. After thermal treatment, FexOy/NC‐MOG films possess uniformly distributed FexOy nanoparticles and larger accessible surface areas than traditional FexOy‐NC films without MOG. Taking advantage of the unique structure, FexOy/NC‐MOG exhibits a superior rate performance (449.8 mA h g?1 at 5000 mA g–1) and long cycle life (629.3 mA h g–1 after 500 cycles at 1000 mA g–1) when used as additive‐free anodes in lithium‐ion batteries. 相似文献
75.
为降低溴冷机中碳钢的腐蚀,通过失重法和电化学方法研究了含有0.07 mol/L LiOH和150mg/L Na2MoO4的55%LiBr、60%LiBr溶液中苯并三氮唑(BTA)对碳钢的缓蚀作用.结果表明,在溴化锂溶液中添加BTA时可显著降低碳钢腐蚀;55%LiBr、60%LiBr溶液中BTA的最佳添加量为100 mg/L;55%LiBr溶液中,BTA通过与铁离子形成Fe-BTA型配合物覆盖在金属表面阻碍浸蚀性Br-吸附而起缓蚀作用;60%LiBr溶液中,BTA则与MoO42-共同作用,在碳钢表面形成MoO2、MoO3和Fe-BTA致密钝化膜减缓金属活性溶解. 相似文献
76.
Construction of Complex Co3O4@Co3V2O8 Hollow Structures from Metal–Organic Frameworks with Enhanced Lithium Storage Properties 下载免费PDF全文
Yan Lu Le Yu Minghong Wu Yong Wang Xiong Wen Lou 《Advanced materials (Deerfield Beach, Fla.)》2018,30(1)
A novel metal–organic‐framework‐engaged strategy is demonstrated for the preparation of multishelled Co3O4@Co3V2O8 hybrid nanoboxes. This strategy relies on the unique reaction of zeolitic imidazolate framework‐67 with the vanadium source of vanadium oxytriisopropoxide. Benefitting from the synthetic versatility, a series of nanostructures can be realized including triple‐shelled and double‐shelled Co3O4@Co3V2O8 nanoboxes and single‐shelled Co3V2O8 nanoboxes. When evaluated as electrode materials for lithium‐ion batteries, these unique hollow structures demonstrate remarkable lithium storage properties. For example, the triple‐shelled Co3O4@Co3V2O8 nanoboxes retain a high capacity of 948 mAh g?1 after 100 cycles at 100 mA g?1. 相似文献
77.
78.
We use an ab initio calculation, within the framework of the density functional theory, to calculate total energy, electronic
energy bands, and the phonon dispersion curves of an fcc structure of lithium as a function of the unit cell volume. We find
that the fcc structure is stable starting from a reduced volume of 0.88 V0, where V0 is the known unit cell volume at ambient pressure and it remains so until a volume of 0.40 V0. The electronic structure and the vibrational modes are calculated, as well as the variation of Tc with the volume. At a reduced volume of 0.40 V0, Tc is calculated to be 20 K, which is in agreement with the experimental value. Our calculations indicate that superconductivity
in Li under high-pressure occurs through intervalley scattering of electrons, between pockets centered at the L-points of
the Brillouin zone (BZ), mediated by phonons in the vicinity of the X-points. 相似文献
79.
利用一步碳热还原法制备了Li3-xNaxV2(PO4)3/C(x=0、0.01、0.02、0.03、0.05、0.08、0.10、0.15)复合正极材料,并用X射线衍射、扫描电镜、红外光谱、循环伏安法、电化学阻抗谱和恒电流充放电技术研究了掺杂对材料结构、微观形貌、充放电性能和Li+脱出嵌入过程的影响。研究表明掺杂少量Na+不影响材料Li3V2(PO4)3的基本结构,但可在Li3V2(PO4)3中形成电子缺陷,提高晶体内部原子的无序化程度,降低极化和电荷转移电阻,从而改善材料的电化学性能。与Li3V2(PO4)3/C相比,Li2.98 Na0.02 V2(PO4)3/C在倍率为15C下的第50次放电容量提高12.1mAh/g,具有较好的倍率性能和循环性能。 相似文献
80.
Lithium‐Ion Batteries: Excimer Ultraviolet‐Irradiated Carbon Nanofibers as Advanced Anodes for Long Cycle Life Lithium‐Ion Batteries (Small 38/2016) 下载免费PDF全文