Electrolyte oxidative stability

Abstract Recent advances in molecular modeling provide significant insight into electrolyte electrochemical and transport properties. The first part of the chapter discusses applications of quantum chemistry methods to determine electrolyte oxidative stability and oxidation-induced decomposition reactions. A link between the oxidation stability of model electrolyte clusters and the kinetics of oxidation reactions is established and compared with the results of linear sweep voltammetry measurements. The second part of the chapter focuses on applying molecular dynamics (MD) simulations and density functional theory to predict the structural and transport properties of liquid electrolytes and solid elecfiolyte interphase (SEI) model compounds the free energy profiles for Uthium desolvation from electrolytes and the behavior of electrolytes at charged electrodes and the electrolyte-SEl interface. 

The result is the formation of a dense and uniform metal oxide layer in which the deposition rate is controlled by the diffusion rate of ionic species and the concentration of electronic charge carriers. This procedure is used to fabricate the thin layer of soHd electrolyte (yttria-stabilized 2irconia) and the interconnection (Mg-doped lanthanum chromite). 

The choice of a suitable oil has special importance. Besides beneficial effects of the oil on the oxidative stability of the separator, other consequences have to be considered. From the chemical mixture of which an oil naturally consists, polar substances may migrate into the electrolyte. Being of lower density than the electrolyte, they accumulate on its surface and may interfere for instance with the proper float function of automatic water refilling systems. Some oils which fully meet both of the above requirements have been identified, i.e., they provide sufficient oxidation stability without generating black deposits [53],... 

Solid oxide fuel cells use zirconium oxide stabilized with yttrium as an electrolyte and have an OT of 850 to 1000°C. 

A1 is thermodynamically unstable, with an oxidation potential at 1.39 V. Its stability in various applications comes from the formation of a native passivation film, which is composed of AI2O3 or oxyhydroxide and hydroxide.This protective layer, with a thickness of 50 nm, not only stabilizes A1 in various nonaqueous electrolytes at high potentials but also renders the A1 surface coating-friendly by enabling excellent adhesion of the electrode materials. It has been reported that with the native film intact A1 could maintain anodic stability up to 5.0 V even in Lilm-based electrolytes. Similar stability has also been observed with A1 pretreated at 480 °C in air, which remains corrosion-free in LiC104/EC/ DME up to 4.2 However, since mechanical... 

The first Ag(II) compound to be isolated in the solid state was tetra-kis(pyridine)silver(2 +) peroxydisulfate.13,14 Its stability can be attributed to its insolubility, the coordination of the Ag(II) ion, and the presence of an anion with an element in a high oxidation state. It can be prepared conveniently, rapidly, and in high yield by reaction of a solution containing silver nitrate and pyridine with a solution of potassium peroxydisulfate. The corresponding, but less stable, nitrate can be prepared by the electrolytic oxidation of silver nitrate in concentrated aqueous pyridine.15... 

Hexa.cya.no Complexes. Ferrocyanide [13408-634] (hexakiscyanoferrate-(4—)), (Fe(CN)6)4", is formed by reaction of iron(II) salts with excess aqueous cyanide. The reaction results in the release of 360 kJ/mol (86 kcal/mol) of heat. The thermodynamic stability of the anion accounts for the success of the original method of synthesis, fusing nitrogenous animal residues (blood, hom, hides, etc) with iron and potassium carbonate. Chemical or electrolytic oxidation of the complex ion affords ferricyanide [13408-62-3] (hexakiscyanoferrate(3—)), [Fe(CN)6]3-, which has a formation constant that is larger by a factor of 107. However, hexakiscyanoferrate(3—) cannot be prepared by direct reaction of iron(III) and cyanide because significant amounts of iron(III) hydroxide also form. Hexacyanoferrate(4—) is quite inert and is nontoxic. In contrast, hexacyanoferrate(3—) is toxic because it is more labile and cyanide dissociates readily. Both complexes liberate HCN upon addition of acids. 

Photosensitized Electrolytic Oxidation of Iodide Ions on Cadmium Sulfide Single Crystal Electrode. The stability of CdS probe under irradiation in an electrolyte containing iodide species. Rotating ring disk voltammetry was used as the methodology. 487... 

Quantitative study of ECL systems is a rather difficult task. The combined requirements of reductant and oxidant stability with high fluorescence efficiency of the parent molecule drastically limit the types of compounds suitable for use in the study of the ECL phenomenon. To these, we must add solubility and chemical stability in the presence of electrodes, electrolyte, and solvent. Photochemical stability is an additional requirement. Chemical complications following the initial electron transfer to and from the electrode are still a problem. The chemistry occurring in solution after electrolysis must therefore be examined carefully. Especially, the solvent-supporting electrolyte system should be chosen to prevent lack of reactivity with the electrogenerated species. All of the above complications may lead to misinterpretation of the essentially simple processes of electron transfer excitation. However, in some cases most of these interferences may be removed by... 

SOLID ELECTROLYTES FROM STABILIZED ZIRCONIUM OXIDE THAT ARE DEVELOPED IN O.J.S.C. UKRAINIAN RESEARCH INSTITUTE OF REFRACTORIES NAMED AFTER A.S. BEREZHNOY ... 

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