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Small controlled amounts of palladium were electrochemically deposited onto various carbon supports from solutions of glycinate-chloride complexes of palladium(II) in order to obtain palladium catalysts suitable for use in fuel cells. The catalytic activity of the resulting catalytic layers was studied in reactions of reduction of atmospheric oxygen and oxidation of methanol and ethanol in acid and alkaline media by measuring cyclic voltammetric curves on a rotating disk electrode. [ABSTRACT FROM AUTHOR]

The behavior of molybdenum(III), tungsten(IV), and uranium(VI) ions in NaCl-2CsCl-eutectic-mixture-based melt at 550°C is studied by spectroelectrochemical method. Anodic oxidation of MoCl and WCl yields melt-soluble chloride compounds MoCl and WCl respectively. It is shown that the electrochemical recharging in the Mo(III)/Mo(IV) system is reversible; the formal standard potential E*Mo(IV)/Mo(III)and the Gibbs energy $$ \Delta G_{MoCl_4 (melt)}^* $$ are evaluated. The cathodic reduction of U(VI) yields U(V) ions. The cathodic reduction of W(IV) ion does not yield melt-soluble tungsten compounds of lower oxidation state. [ABSTRACT FROM AUTHOR]

Abstract  Carbon supported Pt-TiO2(Pt-TiO2/C) catalysts were prepared with colloidal and chemical reduction method on different conditions and used for ethanol electrooxidation in acidic solution. The size of TiO2 and Pt crystal varied on the catalysts prepared by different methods and the Electrochemical specific surface area (ESA) also showed different on these catalysts. The catalytic activity on these carbon supported Pt-TiO2 catalysts showed some different behaviors. [ABSTRACT FROM AUTHOR]

Abstract  A β-4-(2-isopropyl-5-methylphenoxylphthalocyaninato)titanium(IV) oxide (TiOPc) was prepared and characterized by MS, 1H NMR, and elemental analysis. Cyclic voltammograms show that this TiOPc has two quasi-reversible reduction couples and two quasi-reversible to irreversible oxidations processes. The first reductions are two-electron processes, confirmed by spectroelectrochemistry to be due to TiIVPc2−/TiIIIPc3− redox processes. The second reductions are two-electron processes during which TiIIIPc3− was reduced to TiIIIPc5− species. Spectroelectrochemistry showed that oxidation occurs at the ring during the first oxidation. However, spectroelectrochemistry also showed that upon the second oxidation, the molecule decomposes. Chronocoulometry confirmed transfer of two electrons at the first and second reduction steps. [ABSTRACT FROM AUTHOR]

Electrochemical studies of thiol-capped semiconductor nanocrystals have demonstrated several distinct oxidation and reduction peaks in the voltammograms with the peak positions being nanocrystal size dependent. It is demonstrated that the method is very sensitive to the nanocrystal surface states, providing complimentary information for better understanding the optical properties of semiconductor nanocrystals. [ABSTRACT FROM AUTHOR]

There is considerable interest in the use of ruthenium as an ultrathin trench liner in damascene copper plating used to fabricate on-chip interconnects. The problem is that when freshly deposited ruthenium films are exposed to air, their surfaces tend to undergo spontaneous oxidation, and such deposits (as demonstrated here) are reluctant to undergo reduction. Copper deposition in an acid plating bath occurs readily on the oxidized ruthenium, but the presence of oxide is known to have a detrimental effect both on the copper superfilling process and copper adhesion at the Ru/Cu interface. [ABSTRACT FROM AUTHOR]

The electrochemical behavior of titanium dioxide (TiO2) in aqueous lithium hydroxide (LiOH) electrolyte has been investigated. Cyclic voltammetry shows that electroreduction results in the formation of a number of products. X-ray diffraction of the electroreduced TiO2 shows that Li x TiO2, Ti2O3, Ti2O and TiO are formed. The formation of Li x TiO2 is confirmed through X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) studies of the electroreduced TiO2. The formation of Li x TiO2 is electro reversible. In this respect, the electrochemical behavior of TiO2 in concentrated aqueous lithium hydroxide electrolyte is similar to that for lithium perchlorate (LiClO4) non-aqueous media. [ABSTRACT FROM AUTHOR]