Titanium oxide electrochemical behavior

Like their isoelectronic ferrocene counterparts, cobaltocenium units are resistant to strong oxidizing agents and possess interesting electrochemical behavior. The synthesis of polyesters and polyamides containing cationic cobalt units in the main chain has been reported (32,74-76). Sheats and Carraher reported the synthesis of cobaltocenium polymers containing tin, antimony, titanium, and zirconium atoms in their backbone via the reaction of the dicarboxylic... 

In the assessment of the refining performance of uranium, systematic data has been reported for the chemical properties of uranium complex in various alkali chlorides such as LiCl-RbCl and LiCl-CsCl mixtures [3-5], Information on the coordination circumstance of solute ions is also important since it should be correlated with stability. The polarizing power of electrolyte cations controls the local structure around neodymium trivalent Nd " " as an example of f-elements and the degree of its distortion from octahedral symmetry is correlated with thermodynamic properties of NdClg " complex in molten alkali chlorides [6]. On the other hand, when F coexists with Cr in melts, it is well-known that the coordination circumstances of solute ions are drastically changed because of the formation of fluoro-complexes [7-9]. A small amount of F stabilizes the higher oxidation states of titanium and induces a negative shift in the standard potentials of the Ti(IV)ITi(ni) and Ti(III)ITi(II) couples [7, 8], The shift in redox potentials sometimes causes specific electrochemical behavior, for example, the addition of F to the LiCl-KCl eutectic leads to the disproportionation of americium Am into Am " and Am metal [9],... 

Castrillejo et al. studied solubility of several oxides in CaCl2-NaCl equimolar mixture. The solubility product of MgO in the molten CaCl2-NaCl equimolar mixture at 575°C was found to be pK = 5.3 0.1 (molality). Investigations of electrochemical behavior of Ti in the same melt at 500°C permitted to estimate of the solubility products of titanium oxides at lower oxidation degrees of Ti. They were (molality) pis jio = 9.01 and pKj 25.7. These data confirm that the dissociation of the titaninm oxides in this... 

Augustynski, J. Aspects of Photo-Electrochemical and Surface Behavior of Titanium(IV) Oxide. Vol. 69, pp. 1-61. 

The electrochemistry of Ti2+ in 66.7 m/o AlCl3-NaCl has been investigated wherein the electroactive Ti2+ was prepared by the oxidation of Ti metal with liquid A1C13 [176, 185] and by the electrochemical dissolution of titanium metal [120, 177], The authors of both studies concluded that Ti2+ may be oxidized stepwise to Ti3+ and Ti4+ and that both processes are reversible at platinum and tungsten electrodes. However, anomalous voltammetric behavior at high Ti2+ concentrations (greater than 50 mmol L ) suggests the formation of polymeric Ti2+ species in the melt. The reduction of Ti2+ to the metal was not observed at potentials more positive than that required for aluminum deposition. 

The electrochemical reduction behavior of 1102 was also studied in a nitric acid-hydrazine solution at a titanium electrode because of its resistance to corrosion in nitric acid [59]. It was necessary to pretreat the titanium electrode, to remove surface oxide, through cathodic... 

From the Nernst equation, proton-coupled electron addition leads to a - 59 mV shift in potential per pH unit. Figure 15 shows the behavior of titanium dioxide and Figure 16 shows the behavior of tin oxide. The plots comprise Pour-baix diagrams for these materials. The breaks observed at extreme pHs with 2 define pAfa s for TitvO(OH) and TimO(OH), with the relevant electrochemical equilibrium at less extreme pH or 0 values [ — 8 < pH ( 0) < 23] described by [78]... 

In contrast to the processes described above, the electrooxidation of metals and alloys still cannot be considered as an accepted electrosynthetic method as yet only its principal possibilities have been demonstrated. At the same time, the anodic oxidation of transition metals, which forms the basis for a number of semiconductor technologies, is extremely effective and convenient for varying and controlling the thickness, morphology, and stoichiometry of oxide films [233]. It therefore cannot be mled out that, as the concepts concerning the anodic behavior of metal components of HTSCs in various media are developed, new approaches will be found. The development of combined methods that include anodic oxidation can also be expected, by analogy with hydrothermal-electrochemical methods used for obtaining perovskites based on titanium [234,235], even at room temperature [236]. 

N.S. Choudhury, H.C. Graham, J.W. Hinze Oxidation Behavior of Titanium Aluminides, Z.A. Foroulis, F.S. Pettit, Eds., Proceedings of the Symposium on Properties of High Temperature Alloys (Tlte Electrochemical Society, Princeton, N.J.), (1976), pp. 668. 

Avasarala, B. Haidar, P. Electrochemical oxidation behavior of titanium nitride based electrocatalysts under PEM fuel-cell conditions. Electrochim. Acta 55 (2010), pp. 9024-9034. 

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