A broad review of recent research work on the preparation and the remarkable properties of intercalation compounds of graphite, covering a wide range of topics from the basic chemistry, physics and materials science to engineering applications.

Intercalation compounds of graphite

Note: Times Cited: 875 Reference EPFL-ARTICLE-206025doi:10.1021/cr0501846View record in Web of Science URL: ://WOS:000249839900009 Record created on 2015-03-03, modified on 2017-05-12

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Complex hydrides for hydrogen storage.

Although the rechargeable lithium–sulfur battery is an advanced energy storage system, its practical implementation has been impeded by many issues, in particular the shuttle effect causing rapid capacity fade and low Coulombic efficiency. Herein, we report a conductive porous vanadium nitride nanoribbon/graphene composite accommodating the catholyte as the cathode of a lithium–sulfur battery. The vanadium nitride/graphene composite provides strong anchoring for polysulfides and fast polysulfide conversion. The anchoring effect of vanadium nitride is confirmed by experimental and theoretical results. Owing to the high conductivity of vanadium nitride, the composite cathode exhibits lower polarization and faster redox reaction kinetics than a reduced graphene oxide cathode, showing good rate and cycling performances. The initial capacity reaches 1,471 mAh g−1 and the capacity after 100 cycles is 1,252 mAh g−1 at 0.2 C, a loss of only 15%, offering a potential for use in high energy lithium–sulfur batteries. Lithium sulfur batteries are a promising next generation storage technology. Their performance, however, is subject to the parasitic shuttle effect. Here the authors report a cathode material comprising porous vanadium nitride nanoribbon and graphene to provide anchoring for polysulfides.

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Conductive porous vanadium nitride/graphene composite as chemical anchor of polysulfides for lithium-sulfur batteries

http://www.iop.cas.cn/xwzx/kydt/201106/P020110621599779785576.pdf

The superconductivity at 18 K in LiFeAs system

Since their market introduction in 1991, lithium ion batteries (LIBs) have developed evolutionary in terms of their specific energies (Wh/kg) and energy densities (Wh/L). Currently, they do not only dominate the small format battery market for portable electronic devices, but have also been successfully implemented as the technology of choice for electromobility as well as for stationary energy storage. Besides LIBs, a variety of different technologically promising battery concepts exists that, depending on the respective technology, might also be suitable for various application purposes. These systems of the “next generation,” the so-called post-lithium ion batteries (PLIBs), such as metal/sulfur, metal/air or metal/oxygen, or “post-lithium technologies” (systems without Li), which are based on alternative single (Na+, K+) or multivalent ions (Mg2+, Ca2+), are currently being studied intensively. From today’s point of view, it seems quite clear that there will not only be a single technology for all applications (technology monopoly), but different battery systems, which can be especially suitable or combined for a particular application (technology diversity). In this review, we place the lithium ion technology in a historical context and give insights into the battery technology diversity that evolved during the past decades and which will, in turn, influence future research and development.

Lithium ion, lithium metal, and alternative rechargeable battery technologies: the odyssey for high energy density

Ternary phases have been prepared from lithium, another metal, and nitrogen, phosphorus, or arsenic. The ternary compounds, in particular the nitrides, are thermally more stable than the binary compounds. The lithium gives rise to a relatively high polar bonding component. At high temperatures, lithium and the second metal are often randomly distributed among the interstices of the metalloid lattice. The ordering processes that take place with decreasing temperature are investigated by X-ray and magnetic methods and by differential thermal analysis. The phases are classified on a structural basis into seven groups.

Ternary Nitrides, Phosphides, and Arsenides of Lithium

1
Es wurden TiNJ und je zwei Modifikationen von ZrNCl und ZrNBr, ferner TiNCl und TiNBr hergestellt. Die Praparate wurden durch Ammonolyse der Tetrahalogenide bei erhohter Temperatur erhalten.

2
Die Nitridhalogenide sind leicht hydrolisierbar und thermisch wenig bestandig, das Minimum der Bestandigkeit liegt beim TiNJ. Eine Sonderstellung haben die Hochtemperaturmodifikationen β-ZrNCl und β-ZrNBr, die thermisch und chemisch sehr widerstandsfahig sind.

3
Die Kristallstrukturbestimmung ergab fur α-ZrCl, α-ZrNBr, TiNCl, TiNBr und TiNJ den EO5-Typ Raumgruppe D (FeOCl).





1
TiNCl, TiNBr, TiNJ and (both having two modifications) ZrNCl and ZrNBr have been prepared ammonolyzing the corresponding tetrahalides at elevated temperatures.

2
The nitride halides are easily hydrolized and are not very stable against thermal decomposition; TiNJ is the least stable compound. A special case are the high-temperature modifications β-ZrNCl and β-ZrNBr which are very stable against thermal and chemical attack.

3
The EO5-type, space group D (FeOCl-type) is found for α-ZrNCl, α-ZrNBr, TiNCl, TiNBr and TiNJ.

Über Nitridhalogenide des Titans und Zirkons

Die Kristallstruktur des Lithiumamids wurde neu bestimmt. LiNH2 kristallisiert tetragonal mit den Gitterkonstanten: 






Die Elementarzelle enthalt 8 Formeleinheiten. Die Raumgruppe ist I4. Die Atome besetzen folgende Punktlagen: 






Die Anionen sind deformiert kubisch dicht angeordnet. In Tetraederlucken befinden sich die Kationen. Die ungewohnliche Verteilung der Kationen in dieser Verbindung steht in Zusammenhang mit der Ausrichtung des NH-Anions im Gitter des LiNH2.



The crystal structure of Lithiumamide has been reinvestigated. The compound crystallizes tetragonally. The lattice spacings are: a = 5,037 A, c = 10,278 A und c/a = 2,041.



The unit cell contains 8 formula units. The space group is I4. Positions of the atoms see “Inhaltsubersicht”.



The nitrogen has a distorted cubic close-packed arrangement. The cations occupy tetrahedral interstices. The somewhat unusual distribution of cations in this compound may be explained on the basis of the orientation of the NH-ions within the structure of LiNH2.

Neubestimmung der Kristallstruktur des Lithiumamids

1. Die IR-Spektren folgender Verbindungen werden mitgeteilt: M(NH2)2 mit M = Be, Mg, Ca, Sr, Ba, Eu, Yb; M(NH) mit M = Be, Mg, Ca, Sr, Ba; M(NH2)3 mit M = La. Y, Yb; Na[N(NH2)4)] mit M = Gd, Y, Yb; Na3[M(NH2)6] mit M = La, Gd, Y Yb.



2. Durch thermischen Abbau von Amiden erhaltene Mischkristalle werden unter-sucht.



3. Die Valenzkraftkonstante der NH-Bindung steigt mit abnehmendem Radius und zunehmender Ladung des Kations, bedingt durch die zunehmende polarisierende Wirkung des Kations. In den Amidometallaten erniedrigen die Na+-Ionen die Kraftkonstante und die polarisierende Wirkung des zentralen Kations.



IR Spectra of Amides and Imides of Divalent and Trivalent Metals



1. The IR spectra of the following compounds are reported: M(NH2)2 mit M = Be, Mg, Ca, Sr, Ba, Eu, Yb; M(NH) with M = Be, Mg, Ca, Sr, Ba; M(NH2)3 with M = La. Y, Yb; Na[N(NH2)4)] with M = Gd, Y, Yb; Na3[M(NH2)6] with M = La, Gd, Y Yb.



2. Mixed crystals. prepared by thermical desintegration of amides, are studied.



3. The valence-force-constant of the NH bonding rises with decreasing radius and increasing electric charge of the cation, depending on the polarizing action of the cation. In the amidometallates the Na+ ions degrade the force-constant and the polarizing action of the central cation.

Robert Juza

Papers

Ternary Nitrides, Phosphides, and Arsenides of Lithium

Über Nitridhalogenide des Titans und Zirkons

Neubestimmung der Kristallstruktur des Lithiumamids

IR-Spektren von Amiden und Imiden zwei- und dreiwertiger Metalle

Lithium-Graphit-Einlagerungsverbindungen