Cathode preparation

Lee S, Lim Y, Lee EA, Hwang HJ, and Moon JW. Ba0 5Sr05Co0 8Fe02O3 5 (BSCF) and Lao6Ba04Co02Fe0803 5 (LBCF) cathodes prepared by combined citrate-EDTA method for IT-SOFCs. J. Power Sources 2006 157 848-854. 

Huang Y, Vohs JM, and Gorte RJ. SOFC cathodes prepared by infiltration with various LSM precursors. Electrochem. Solid State Lett. 2006 9 A237-A240. 

Hsu CS and Hwang BH. Microstructure and properties of the La06Sr04Co02Fe08O3 cathodes prepared by electrostatic-assisted ultrasonic spray pyrolysis method. J. Electrochem. Soc. 2006 153 A1478-A1483. 

Reduction in aptotic solvents may be accompanied by side reactions due to the alkaline conditions developed around the cathode. Preparative work is thus limited to substrates undergoing these unwanted side reactions relatively slowly. Reductive dimerizations in aptotic solvents show a high degree of stereoselectivity in favour of carbon-carbon bond formation to yield the ( )-isomer. A templating action is brought about either by co-ordination to a lithium or sodium ion of two reacting... 

Tire electrical method, commonly applied to the preparation of colloidal metals, can also be extended to selenium. When an electric discharge is made to pass under pure water between a platinum anode and a cathode prepared by fusing a small piece of selenium on to platinum foil, colloidal selenium is slowly formed.6 When a dilute solution of selenious anhydride is electrolysed using platinum electrodes, a colloidal solution of selenium and a black cathodic deposit of selenium... 

New approaches to the synthesis of SVO cathode material have been reported. In 1995, Takeuchi and Thiebolt patented a new preparation for SVO cathodes prepared via addition of elemental silver to vanadium compounds present in an anhydrous mixture. Oxygen-deficient SVO compounds were found, as well as compounds designed to provide a desired shape in the electrical discharge curve of the cell [59], Following this work in 1996, Takeuchi and Thiebolt patented several methods for the preparation of amorphous SVO prepared by chemical addition reaction at temperatures high enough to melt the mixture, coupled with rapid cooling... 

Anodic and cathodic electron transfer is the elementary process underlying all electrolytic reactions, and is followed by chemical reactions of the intermediates formed in the majority of cases. In cases where the intermediate is stable under the prevailing reaction conditions, anodic or cathodic preparation of radical ions, radicals, or ions is possible. The electrolytic method is here often superior to chemical methods, since work-up is not complicated by the presence of any inorganic redox couple. 

NEW TECHNIQUE OF FIELD EMISSION CATHODES PREPARATION BY LOW TEMPERATURE DEPOSITION FROM ETHANOL VAPOR... 

Fig. 6. Scheme of the laser-driven RF electron accelerator of pulse radiolysis facility ELYSE. IP ion vacuum pump, CPC cathode preparation chamber, W vacuum valve, SOL solenoid, D dipole, TRl and 2 triplets, Q quadrupole, WCM wall current monitor, PC Faraday cup, T translator for Cerenkov light emitter and visualization screen LME laser entrance mirror, LMEx laser exit mirror, VC virtual cathode FIS horizontal slit, VS vertical slit. (Reproduced with permission from Ref 28.)... 

Such electrodes have mostly been used as anodes, but cathodic redox catalysis is also possible. In Ti/Ti02 composite cathodes, prepared by the ceramic method, Ti(OH)4 is... 

Arewgoda and coworkers [258] reported a cathodic preparation of a stereoisomer of (CF3 )6QCO2(Co)o [P(OMe)3]2 complex. 

Indeed, it has been demonstrated 88) that Cs suboxides are of essential importance in the famous infrared sensitive SI photocathode 89). These cathodes contain a thin layer of oxidized Cs on a silver substrate. It is evident from UPS measurements on such a cathode prepared in a PE spectrometer that the Cs—0 layer is essentially composed of Csj 1O3, or a higher oxidized, but still metallic suboxide, giving rise to the characteristic spectrum of the bulk material, although the layer has only the thickness of a few atoms. 88) The high yield of photoelectrons in the near infrared with the SI photocathode results from two effects CS11O3 is characterized by a sufficiently small work function (emit photoelectrons when irradiated with infrared light. Furthermore, the energy necessary to create surface plasmons... 

The cathode formulations further employ metallic catalysts to promote the recombination of hydrogen gas generated within the zinc anode at very low (0.025 %) or zero mercury content [41,42,43]. The hydrogen scavenger can form a discrete auxiliary electrode in electronic contact with the cathode or can be introduced simply as a cathode additive in a ratio of 30/70 in the cathode preparation process. A very reliable catalytic material even at elevated temperatures (65°C) is Ag20. The auxiliary electrode may be an annulus or a disk of similar... 

Polythiophene (PTh) and its derivatives are unique in that they can be prepared both anodically and cathodically. Anodic preparation of PTh was first mentioned by Diaz et al [21b] during their oxidation experiments of aromatic oligomers and monomers, which was followed by Tourillon and Gamier s work in 1982 [24], The cathodic preparation of PTh is not as straightforward and requires the reduction of an organometallic complex, such as (2-bromo-5-thienyl)-tri-phenylnickel dibromide [25]. 

Chaparro AM, Benitez R, Gubler L, Scherer GG, Daza L. Study of membrane electrode assembUes for PEMFC, with cathodes prepared by the electrospray method. J Power Sources 2007 169(1) 77—84. 

Electrodeposition - Electrolytic reduction of plutonium at a platinum cathode. Preparation of sources for energy analysis. Very thin, uniform films arc attainable. Method can be made quantitative. Requires special preparation of solution, requires relatively long time to prep2irc 1 sample. 

The reversible process of recharge [10] of the Cr(III) complexes to Cr(II) ones is not observed at the platinum electrode, and is clearly observed at the cathode prepared from glassy carbon (Fig. 1). 

A fuel cell reactor was designed for oxidation of ethylene with O2, as shown in Fig. 1. The cell was assembled using a membrane anode prepared from Pd-black supported carbon, a membrane cathode prepared from Pt-black supported carbon, and an electrolyte membrane of H3PO4/ Si02-wool. Selective oxidation of ethylene to acetaldehyde with a 95 % selectivity was performed using ethylene-02 fuel cell reaction at 373 K. Electrocatalysis of the Pd/C anode for the partial oxidation of ethylene is essential [1,4]. 

Yamanaka I, Hashimoto T, Otsuka K (2002) Direct synthesis of hydrogen peroxide (>lwt%) over the cathode prepared from active carbon and vapor-grown-carbon-fiber by a new H2-O2 fuel cell system. Chem Lett 8 852-853... 

Yamanaka I, Hashimoto T, Ichihashi R, Otsuka K (2008) Direct synthesis of H2O2 acid solutions over carbon cathode prepared from activated carbon and vapor-growing-carbon-fiber by a H2/O2 fuel cell. Electrochim Acta 53 4824—4832... 

Vohs JM, Gorte RJ (2009) High-performance SOFC cathodes prepared by infiltration. Adv Mater 21(9) 943-956... 

Lee S, Beviiacqua M, Fomasiero P, Vohs JM, Gorte RJ (2009) Solid oxide fuel ceil cathodes prepared by infiltration of LaNio.6Feo.4O3 and Lao,, 9iSro. 09Ni0.6Fe0.4O3 in porous yttria-stabilized zirconia. J Power Sources 193 747-753... 

Figure 23 Comparison of the IR spectra of pure EC (a), the electrolyte (b), and electrolyte residue on different substrates (c) commercial liCoOa (d) nano-MgO (e) nano-MgO coated LiCoOa (f) the binder fa- cathode preparation (the strong bands around 600 cm in c are characteristic bands of commercial liCoOa). Reproduced from [122] with permission of The Electrochemical Society Inc.

Leng, Y.J., Chan, S.H., Khor, K.A. Jiang, S.P. (Lao.8Sro.2)o.9Mn03-Gdo.2Ceo.80i.9 composite cathodes prepared from (Gd,Ce)(N03)j modified (Lao.8Sro.2)o.9Mn03 for intermediate-temperature solid oxide fuel-cells. J. Solid State Electrochem. 10 (2006), pp. 339-347. 

Zhang, L., Zhao, E, Peng, R.R. Xia, C.R. Effect of firing temperature on the performance of LSM-SDC cathodes prepared with an ion-impregnation method. Solid State Ionics 179 (2008), pp. 1553-1556. 

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