Platinum-tungsten

Zinc and tin The electrodeposition of Zn [52] has been investigated in acidic chloroaluminate liquids on gold, platinum, tungsten, and glassy carbon. On glassy carbon only three-dimensional bulk deposition was observed, due to the metal s underpotential deposition behavior. At higher overvoltages, codeposition with A1... 

Ey and E2 are the indicator electrodes. These may consist of a tungsten pair for a biamperometric end point for an amperometric end point they may both be of platinum foil or one can be platinum and the other a saturated calomel reference electrode. The voltage impressed upon the indicator electrodes is supplied by battery B (ca 1.5 volts) via a variable resistance Rs N records the indicator current. For a potentiometric end point Ey and E2 may consist of either platinum-tungsten bimetallic electrodes, or Ey may be an S.C.E. and E2... 

A platinum-rhenium composite catalyst supported on the granular activated carbon (Pt-Re/C, 5 wt-Pt%, mixed molar ratio of Pt/Re = 2) [10] was prepared by a "dry-migration method" [33,34] as follows (1) The Pt/C catalyst prepared earlier (5 wt-metal%) was evacuated at 180°C for 1 h (2) The mixture (molar ratio of Pt/Re = 2) of the Pt/C catalyst and a cyclopentadienylrhenium tricarbonyl complex (Re(Cp)(CO)3) were stirred under nitrogen atmosphere at room temperature for 1 h and then heated at 100° for 1 h, with the temperature kept at a constant (3) This mixture was further stirred under hydrogen atmosphere at 240°C for 3 h and finally (4) the Pt-Re/C composite catalyst was evacuated at 180°C for 1 h. A platinum-tungsten composite catalyst supported on the granular activated carbon (Pt-W/C, 5 wt-Pt%, mixed molar ratio of Pt/W = 1) [5,6] was also prepared similarly by the dry-migration method. All the catalysts were evacuated inside the reactor at 150°C for 1 h before use. 

Palmer (Proo. Poy. 8oc. A, cvi. 200,1924) in investigating the effect of various gases on the sensitiveness of a coherer or loose contact has noted that the potential required to break down the loose contact between platinum, tungsten and carbon films varies with the nature of the gas. 

In an interesting recent work [36], a [EMIM][BF4] ionic Hquid with added [EMIM]Cl was successfuUy used to deposit Cd. It is formed on platinum, tungsten, and glassy carbon from CdCl4 in a quasireversible two-electron reduction process. This result is promising, as Te might perhaps also be deposited from such an ionic Hquid, thus possibly giving a system for direct CdTe electrodeposition. 

Researchers at NASA (National Aeronaulics and Space Administration. Cleveland. Ohio) tested a large number of alloys, such as irun-chromium-aluminum. platinum-tungsten, platinum-palladium-molybdcnum, and palla... 

Platinum-tungsten clusters, as heterogeneous catalyst precursors, 12, 769... 

Some of the materials that have been examined as catalysts include Pure Platinum, Platinum-Iridium Alloys, Various Compositions of Platinum-Rhodium Alloys, Platinum-Palladium Alloys, Platinum-Ruthenium Alloys, Platinum-Rhenium Alloys, Platinum-Tungsten Alloys, FejOj-M CVI Oj (Braun Oxide), CoO-Bi20j, CoO with AI2O3, Thorium, Cerium, Zinc and Cadmium. 

Tables 21 and 22 (and Figure 8) review Pt chemical shifts and metal-metal coupling constants of several chain clusters containing platinum, tungsten, nickel and molybdenum [119-121]. Likewise, Table 23 presents similar data for cyclic clusters containing eight metal atoms [120,122]. All these results are used to provide evidence of the structures, the symmetry and the isomerism of the clusters in solution.

O. Savadogo, P. Beck, Five percent platinum-tungsten oxide-based electrocatalysts for phosphoric acid fuel cell cathodes. J. Electrochem. Soc. 1996, 143(12), 3842-3846. 

An alternative method for the visualization of small structures is shadowing with heavy metals (platinum, tungsten, etc.). Rotary shadowing in combination with the surface spreading technique of Kleinsmidt [7] appeared to be very powerful. In this method macromolecules are decorated with platinum grains of about 40 A which indirectly visualize the shape of these molecules. Double-stranded and even single-... 

Hsu IJ, Kimmel YC, Jiang XJ, Willis BG, Chen JG (2012) Atomic layer deposition synthesis of platinum-tungsten carbide core-shell catalysts for the hydrogen evolution reaction. Chem Commun 48 1063-1065... 

Kariya et al. performed dehydrogenation of methylcyclohexane and other cycloalkanes over platinum, palladium and rhodium monometallic and platinum/palladium, platinum/rhodium, platinum/molybdenum, platinum/tungsten, platinum/rhenium platinum/osmium and platinum/iridium catalysts supported on both petroleum coke active carbon and on alumina between 375 and 400 °C [279]. The platinum catalyst supported by petroleum active carbon showed the highest activity. While platinum was the most active monometallic catalyst, its activity could be increased by addition of molybdenum, tungsten and rhenium. 

Maiyalagan, T. and Viswanathan, B. 2008. Catalytic activity of platinum/tungsten oxide nanorod electrodes towards electro-oxidation of methanol. Journal of Power Sources 175 789-793. 

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