Anode preparation

C) method of anode preparation (metal, metal oxide, or hydroxide + subsequent reduction, other metal compounds + reduction, etc.). 

Chemical reduction of an ore usually gives metal that is not pure enough for its intended use. Further refining of the metal removes undesirable impurities. Several important metals, including Cu, Ni, Zn, and Cr, are refined by electrolysis, either from an aqueous solution of the metal salt or from anodes prepared from the impure metal. To give one example, ions, obtained by dissolving ZnS or ZnO in acidic solution, can be reduced while water... 

Li N.C., Martin C.R. A high-rate, high-capacity, nanostructured Sn-based anode prepared using sol-gel template synthesis. J Electrochem. Soc.2001 148(2) A164-70. 

FIGURE 2.12 Effect of Ni content on the electrode/electrolyte interface conductivity (aE) and the ohmic resistance (Wohm) for Ni-YSZ cermet anodes prepared using NiO-YSZ powder mixtures precalcinated at 1400°C and sintered at 1500°C. (From Kawada, T. et al.,./. Electrochem. Soc., 137 3042-3047, 1990. Reproduced by permission of ECS-The Electrochemical Society.)... 

The influence of porosity on the electrochemical activity has not been studied much for electrolyte-supported cells because anode pastes for electrolyte-supported cells are made for screen printing, and thus contain significant amounts of organics, which almost guarantees sufficient porosity. In addition, since the anode thickness for electrolyte-supported cells is only on the order of 50 pm, the concentration polarization itself becomes much less of an issue. In fact, Jiang et al. [44] showed that anode overpotential for cermet anodes prepared with extra graphite pore formers... 

Pratihar SK, Baus RN, Mazumder S, and Maiti HS. Electrical conductivity and microstructure of Ni-YSZ anode prepared by liquid dispersion method. In Singhal SC, Dokiya M, editors. Proceedings of the Sixth International Symposium on Solid Oxide Fuel cells (SOFC-VI), Pennington, NJ The Electrochemical Society, 1999 99(19) 513-521. 

Liu Y and Liu M. Porous SOFC anodes prepared by sublimation of an immiscible metal oxide during sintering. Electrochem. Solid State Lett. 2006 9 B25-B27. 

Qiao J, Sun K, Zhang N, Sun B, Kong J, and Zhou DJ. Ni/YSZ and Ni-Ce02/YSZ anodes prepared by impregnation for solid oxide fuel cells. J. Power Sources 2007 169 253-258. 

For example, systems based on [Ru(bipy)3]2+ itself can produce oxygen at pH >7 at a Pt anode,351 whereas smooth oxygen production is observed at pH 4.7 from an anode prepared from Ru02 deposited on titanium sheet.354,358 Still lower pH values for the anode compartment are possible if [Ru(bipy)2L]2+ (L = dipropyl 2,2 -bipyridyl-4,4 -dicarboxylate) for which °(3+/2+) is 1.59 V (vs. SCE).356 There is, however, a suggestion that using Ru02 and [Ru(bipy)3]2+, 02 production can occur from an anode at pH as low as l.O.358... 

M. Marinsek, K. Zupan, J. Maeek, Ni-YSZ cermet anodes prepared by citrate/nitrate combustion synthesis , Journal of Power Sources 106,178-188 (2002). 

Moshtev RA, Zlatilova P, Puresheva B, Manev V, Kozawa A. Cycling performance of the LixAl anode prepared by the compression method. J Power Sources 1994 51 409-423. 

Fig. 14.3 XRD patterns of Ti/Sn02-Sb anodes prepared at different temperature...

Since anodically prepared a-formyloxy-A / -dimethylformamide has successfully been used as an electrophilic reagent, and it has been found that the a-methoxylation of the carbamates of a variety of higher aliphatic amines and alicyclic amines can be readily performed, extensive studies have been carried out to utilize the anodically synthesized a-methoxy- or a-acyloxy-amides and -carbamates as electrophiles in organic synthesis. One example is shown in equation (51). ... 

Brown Boveri Cie and Electrolyzer Corporation achieved a main progress in the mid-1980s with respect to the performance of the alkaline monopolar cells. The first company was able to enlarge the efficiency from 2 to 3.4 kA/m2 with 500 m3/h [13], on the other hand the second company that was able to achieve only 1.74 V reached 134 mA/cm2 at 87% efficiency with nickel-boride materials and NiCo204 anodes (prepared from the freeze-dry technique) [14]. 

Table 1. Anodically Prepared Acid Salts of Graphite...

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]. 

This preparation has been modified by electronic reduction in DMF solution containing 0.3 M Bu4N BF4 as electrolyte in an undivided cell with a platinum cathode and the anode prepared from the expected metal as cation source. 

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