Transition-metal oxide containing

The LIB cathode materials are transition metal oxides containing lithium, and they are a type of functional ceramics. For such a material to be used as LIB cathode, the Li ions must be able to diffuse freely through the crystal stmcture. The morphology of the crystal structure, being one-, two-, or three-dimensional, determines the number of dimensions in which Li ions are able to move. Cathode materials currently in use or under development are described below in accordance with the following three morphologies. 

Metal oxides represent one of the most important and widely employed classes of solid catalysts, either as active phases or as supports. Metal oxides are used for both their acid-base and redox properties and constitute the largest family of catalysts in heterogeneous catalysis [1-6]. The three key features of metal oxides, which are essential for their application in catalysis, are (i) coordination environment of the surface atoms, (ii) redox properties of the oxide, and (iii) oxidation state of the surface. Surface coordination environment can be controlled by the choice of crystal plane exposed and by the preparation procedures employed however, specification of redox properties is largely a matter of choice of the oxide. The majority of oxide catalysts correspond to more or less complex transition metal oxides containing cations of variable oxidation state. These cations introduce redox properties and, in addition, acid-base properties. The acid-base properties of the oxides are usually interrelated to their redox behavior. Many attempts were made... 

Structural Insight into Transition Metal Oxide Containing Glasses by Molecular Dynamic Simulations... 

Transition metal oxide containing zeolites are used in selective oxidation reactions, ammoxidation, aromatization, photocatalysis and the selective catalytic reduction of NO. Often, isolated, zeolite-boimd oxidic species are identified as the most active sites in these reactions. Therefore, the preparation procedures are usually aimed at creating very small intrazeolitic oxide clusters or even isolated metal oxo-spedes. 

Alcohol autoxidation is carried out in the range of 70—160°C and 1000—2000 kPa (10—20 atm). These conditions maintain the product and reactants as Hquids and are near optimum for practical hydrogen peroxide production rates. Several additives including acids, nitriles, stabHizers, and sequestered transition-metal oxides reportedly improve process economics. The product mixture, containing hydrogen peroxide, water, acetone, and residual isopropyl alcohol, is separated in a wiped film evaporator. The organics and water are taken overhead and further refined to recover by-product acetone and the... 

Solid catalysts for the metathesis reaction are mainly transition metal oxides, carbonyls, or sulfides deposited on high surface area supports (oxides and phosphates). After activation, a wide variety of solid catalysts is effective, for the metathesis of alkenes. Table I (1, 34 38) gives a survey of the more efficient catalysts which have been reported to convert propene into ethene and linear butenes. The most active ones contain rhenium, molybdenum, or tungsten. An outstanding catalyst is rhenium oxide on alumina, which is active under very mild conditions, viz. room temperature and atmospheric pressure, yielding exclusively the primary metathesis products. 

Methane-to-methanol conversion by gas-phase transition metal oxide cations has been extensively studied by experiment and theory see reviews by Schroder, Schwarz, and co-workers [18, 23, 134, 135] and by Metz [25, 136]. We have used photofragment spectroscopy to study the electronic spectroscopy of FeO" " [47, 137], NiO [25], and PtO [68], as well as the electronic and vibrational spectroscopy of intermediates of the FeO - - CH4 reaction. [45, 136] We have also used photoionization of FeO to characterize low lying, low spin electronic states of FeO [39]. Our results on the iron-containing molecules are presented in this section. 

Increase the oxidation rate of polymers, e.g. metal ions which increase the hydroperoxide decomposition rate. Photodegradation and thermal degradation are enhanced by transition metal ion containing pro-oxidants, such as iron dithiocarbamate (as opposed to nickel dithiocarba-mate, which acts as a photo-antioxidant). 

Table 4. Reduction of cell volumes of ternary transition metal oxides (M Y OJ relative to the volume of ternary Mg-containing oxides...

This work summarizes some applications of in situ Mossbauer spectroscopy to the study of certain aspects of the electrochemistry of iron and iron containing transition metal oxides. A number of illustrations of the use of this technique to the investigation of a wide variety of interfacial phenomena may be found in two recent monographs. (2 ... 

Chromylchloride, Cr02Cl2, the main subject of the publication which led to the original discussion about the mechanism [12], shows a very different reactivity compared to the other transition metal oxides discussed above. Even in the absence of peroxides, it yields epoxides rather than diols in a complex mixture of products, which also contains cis-chlorohydrine and vicinal dichlorides. Many different mechanisms have been proposed to explain the great variety of products observed, but none of the proposed intermediates could be identified. Stairs et al. have proposed a direct interaction of the alkene with one oxygen atom of chromylchloride [63-65], while Sharpless proposed a chromaoxetane [12] formed via a [2+2] pathway. 

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