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Palladium-based cathode

Fleischmann, M., Pons, S., Anderson, M.W. et al. (1990) Calorimetry of the paUadium-deuterium-heavy water system. Journal of Electrvanalytical Chemistry, 287, 293. Fleischmann, M. and Pons, S. (1991) The calorimetry of electrode reactions and measurements of excess enthalpy generation in the electrolysis of heavy water using palladium based cathodes. Proceedings, Itahan Physics Society Conference, vol. 33, p. 349. [Pg.17]

Multiphase gold or palladium-based alloys never show dissolution of Au or Pd but often exhibit progressive surface ennoblement due to selective dissolution of copper or silver from the outer 2-3 atomic layers Heat treatment often decomposes multicomponent alloys into a Pd-Cu rich compound and an Ag-rich matrix with corrosion of the latter phase in deaerated artificial saliva and S -containing media . Au-Cu-rich lamellae have similarly been observed, again with preferential attack on Ag-rich phases or matrix. These effects presumably arise from the ability of the noble alloy phases to catalyse the cathodic reduction of oxygen . [Pg.462]

Electroplating. Basically in electroplating, a substrate is coated with a metal or its alloy in a plating bath where the substrate is the cathode and the temperature is maintained constant Membranes from a few microns to a few millimeters thick can be deposited by carefully controlling the plating time, temperature, current density and the bath composition. Dense membranes made of palladium and its various alloys such as Pd-Cu have been prepared. Porous palladium-based membranes have also been made by deposition on porous support materials such as glass, ceramics, etc. [Pg.26]

Palladium-based hollow cathode electrolysers for hydrogen production... [Pg.607]

Li HQ, Xin Q, Li WZ, Zhou ZH, Jiang LH, Yang SH, Sun GQ (2004) An improved palladium-based DMFCs cathode catalyst Chem Commun 23 2776-2777... [Pg.532]

Liang, F.L., Chen, X, Jiang, S.P., Chi, B., Pu, J. Jian, L. Development of nanostructured and palladium promoted (La,Sr)Mn03-based cathodes for intermediate-temperature SOFCs. Electrochem. Solid-State Lett. 11 (2008), pp. B213-B216. [Pg.208]

Atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-triazine), a photosynthetic inhibitor that is used in large quantities for weed control in com and sorghum, has been treated electrochemically in aqueous solution on reticulated vitreous carbon cathode in the presence of noble-metal catalysts (Stock and Bunce 2002). Elec-trocatalytic hydrogenolysis to 2-ethylamino-4-isopropylamino-s-triazine occurs in quantitative yield, and is most efficient with Pd-based catalysts. Current efficiency increases with increasing atrazine and catalyst concentration, and decreasing current density. The Authors observed a time lag between the start of the electrolysis and the appearance of the dechlorinated products, which was attributed to the absorption of hydrogen by the palladium lattice. As alternative to the electrochemical treatment, the degradation of chlorinated triazines by zero-valent-iron was already mentioned (Dombek et al. 2004). [Pg.295]

Miscellaneous.—It has been shown that pH measurements can be made in aerated, concentrated solutions of reactive electrolytes (g.g, aqueous NH4F-HF solutions) with Pd electrodes cathodically charged with respect to palladium hydride. Brown has described the reactions of KH with a variety of primary amines thus from trimethylenediamine, the product, potassium 3-aminopropylamide, is soluble in excess base and is claimed to be a novel alkylamide superbase of exceptional reactivity. [Pg.416]

In palladium-silver alloys, larger amounts of hydrogen can be solubilised because the metal lattice has already been expanded by the silver atoms, and thus it is less brittle than the pure Pd lattice. Based on these considerations, the ideal silver content of the Pd cathode is between 20 wt% and 30 wt%. In order to obtain high flow rates of pure hydrogen, the maximum permeability of the Pd-Ag cathode must be realized. The hydrogen permeability P through the lattice of the Pd-Ag tubular electrode follows Sieverts law. The H2 permeating flow rate Qp (mol s ) can be derived from Equation [16.2] ... [Pg.613]

Another approach to improve the durability of the membranes is to place an additional layer for decomposition or trapping of radicals (Burlastsky et al. 2004 Tsurumaki2006). It has been reported that the duiabihty of electrolyte membrane is improved by placing a catalyst layer based on platinum, palladium, iridium, etc. inside the membrane between the anode and the cathode (Burlastsky et al. 2004). Radical-trap layers, which are based on rare earth metal oxides, on both sides of the membrane are also effective, and it has been reported that the durabiUty of the MEA in OCV tests is improved by one order of magnitude compared with the standard MEA (Tsurumaki 2006). [Pg.100]

It was concluded first by Knorr and coworkers [1] that diffusion of molecular hydrogen is the rate-determining step of hydrogen evolution on smooth platinum and palladium electrodes pretreated anodically. The same conclusion holds for the anodic processes given by Eq. 1 and 2. The interpretation based on steady-state measurements [1] is valid at cathodic current densities — i < 1 mA/cm in strong acid electrolytes (0d.H+ 1)- The correctness of this interpretation has been substantiated by a number of independent techniques which allow the concentration Ch2 of H2 molecules adjacent to the surface to be determined ... [Pg.78]

The controlled-potential electrolyses were carried out in a cell with three separated compartments. The cathode was a reticulated carbon rod and the anode was a platinum wire. As reference electrode was used a modified SCE. The catholyte was prepared by dissolving 2-aminophenol in CH3CN, containing n-Bu NBF (0.2M) as well as an excess of base and dichlorobis(triphenylphosphine) palladium(II) or palladium(II) acetate as catalyst. Carbon monoxide was bubbled through a glass capillary into the cathodic solution that subsequently was kept under a CO pressure of 1 atm. The electrolyses were interrupted when the current dropped to the value of the background current. [Pg.94]


See other pages where Palladium-based cathode is mentioned: [Pg.39]    [Pg.513]    [Pg.131]    [Pg.262]    [Pg.138]    [Pg.562]    [Pg.346]    [Pg.166]    [Pg.1095]    [Pg.591]    [Pg.611]    [Pg.608]    [Pg.609]    [Pg.313]    [Pg.584]    [Pg.44]    [Pg.255]    [Pg.656]    [Pg.1158]    [Pg.171]    [Pg.134]    [Pg.202]    [Pg.103]    [Pg.517]    [Pg.1350]    [Pg.517]    [Pg.345]   


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