Mono crystals platinum

The photo-Kolbe reaction is the decarboxylation of carboxylic acids at tow voltage under irradiation at semiconductor anodes (TiO ), that are partially doped with metals, e.g. platinum [343, 344]. On semiconductor powders the dominant product is a hydrocarbon by substitution of the carboxylate group for hydrogen (Eq. 41), whereas on an n-TiOj single crystal in the oxidation of acetic acid the formation of ethane besides methane could be observed [345, 346]. Dependent on the kind of semiconductor, the adsorbed metal, and the pH of the solution the extent of alkyl coupling versus reduction to the hydrocarbon can be controlled to some extent [346]. The intermediacy of alkyl radicals has been demonstrated by ESR-spectroscopy [347], that of the alkyl anion by deuterium incorporation [344]. With vicinal diacids the mono- or bisdecarboxylation can be controlled by the light flux [348]. Adipic acid yielded butane [349] with levulinic acid the products of decarboxylation, methyl ethyl-... 

Adsorption experiments were conducted on chromium, platinum, cadmium, and zinc the sources and preparation of these metal specimens have been reported previously (16). In preparing adsorbed, mono-molecular layers by adsorption directly from the molten pure acid (5), the clean adsorbing substrate was first heated to a temperature just above the melting point of the acid (see Table I), a few crystals of the acid were sprinkled on the surface, and the resulting pool of molten acid was teased over the whole surface with a previously freshly flamed platinum wire. If spontaneous retraction of the liquid acid did not occur, the specimen was allowed to cool and all of the solidified material adhering on top of the adsorbed monolayer was removed by appropriate solvent treatments as discussed below. 

Di-methyl aniline, CeHs—N(CH3)2, is a liquid boiling at the same point as the mono-methyl compound with which it is obtained by the ordinary method of preparation and from which it may be separated by the method just described. It forms well crystallized salts, especially the double salt with platinum chloride, viz., CeHs—N(CH3)2.HCL-PtCh. This compound crystalhzes, with two molecules of water, in ruby colored prisms, which, on loss of water, become reddish-yellow plates. The acid oxalate salt, CeHs—N(CH3)2.(COOH)2, forms large rectangular plates melting at 139°. With nitrous acid the reaction is the one characteristic of aromatic tertiary amines. 

Zhang et al. investigated Pt monolayer deposits on Pd(lll) single crystals (Pt/Pd(lll)) and on Pd/C nanoparticles (Pt/Pd/C) for ORR [18]. The ORR reaction mechanism of the mono-layer catalysts was found to be the same as that on pure Pt surface. Pt/Pd(lll) was found to have a 20 mV improvement in half-wave potential versus Pt(lll), and the Pt/Pd/C had a Pt-mass activity 5-8 times higher than that of Pt/C catalyst. The enhanced ORR activity is attributed to the inhibited OH formation at high potential, as evidenced from XAS measurements. In a real fuel cell test, 0.47gpt/kW was demonstrated at 0.602 V [21]. In a related study, the ORR on platinum monolayers supported on Au(lll),... 

Lu W, Chan MCW, Cheung KK et al (2001) Interactions in organometallic systems. Crystal structures and spectroscopic properties of luminescent mono-, bi-, and trinuclear trans-cyclometalated platinum(II) complexes derived from 2,6 diphenylpyridine. Oiganometallics 20 2477-2486... 

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