Ruthenium plate

Ruthenium compounds, 19 637-641 synthesis of, 19 640 uses for, 19 640—641 Ruthenium-copper clusters, 16 70 Ruthenium initiators, 26 934 Ruthenium plating, 9 823 Ruthenium-silica... 

We have once again probed the essential features of this catalysis through spectroscopic and kinetic measurements. The syntheses are generally believed to be homogeneous since hydrocarbons higher than methane are rarely detected, there is no evidence of ruthenium plating. 

Hu C-C, Chiang H-R, Wang C-C (2003) Electrochemical and structural investigations of oxide films anodicaiiy formed on ruthenium-plated titanium electrodes in sulfuric acid. J Solid State Electrochem 7 477-484... 

Ruthenium is a hard, white metal and has four crystal modifications. It does not tarnish at room temperatures, but oxidizes explosively. It is attacked by halogens, hydroxides, etc. Ruthenium can be plated by electrodeposition or by thermal decomposition methods. The metal is one of the most effective hardeners for platinum and palladium, and is alloyed with these metals to make electrical contacts for severe wear resistance. A ruthenium-molybdenum alloy is said to be... 

Other Metals. Ruthenium, the least expensive of the platinum group, is the second best electrical conductor, has the hardest deposit, and has a high melting point. A general purpose bath uses 5.3 g/L of mthenium as the sulfamate salt with 8 g/L sulfamic acid, and is operated at 25—60°C with a pH of 1—2. Osmium has been plated from acid chloride solutions (130) and iridium from bromide solutions, but there are no known appHcations for these baths. 

For ruthenium, electrolytes based on ruthenium sulphamate or nitrosyl-sulphamate have been described, but the most useful solutions currently available are based on the anionic complex (H2 0 Cl4 Ru N Ru-Cl4-OH2) . The latter solutions operate with relatively high cathode efficiency to furnish bright deposits up to a thickness of about 0-005 0 mm, which are similar in physical characteristics to electrodeposited rhodium and have shown promise in applications for which the latter more costly metal is commonly employed. Particularly interesting is the potential application of ruthenium as an alternative to gold or rhodium plating on the contact members of sealed-reed relay switches. 

The model immunoassay is the enzyme-linked immunosorbent assay (ELISA) in which a non-specific capture antibody is bound to a surface, such as a multi-well plate or small tube [13]. In the basic form of ELISA, a second antibody tagged with an enzyme interacts specifically with the analyte. The enzyme assay produces a colored product that is read with a spectrophotometer. There are many variations on the basic immunoassay format that serve to increase sensitivity, specificity, linear range, and speed. Many commercial instruments have been developed to take advantage of various technologies for reporter molecules. The immunoassay may be coupled to an electronic sensor and transducer, such as a surface acoustical wave (SAW) sensor. Electrochemiluminescence (ECL) is a method in which the detector antibody is tagged with a ruthenium-containing chelate [13-15]. When the tag is... 

To investigate the electrochemical properties of pure ruthenium also, ruthenium was chemically reduced and deposited as a thick layer on a platinum wire becaiise ruthenixim metal is not commercially available as a wire nor a plate due to its brittleness. A platinum wire (0.1 mm in diameter) was placed in an alkaline 0.05 M ruthenium (IQ) nitrosylnitrate solution containing 1 M hydrazine as a reducing agent and heated up to 60°C. The deposition did not start imtil the heat was applied. After the deposition, the electrode was washed with water and used for the electrochemical measurements. 

MesoScale Discovery (MSD) succeeded in introducing product with a similar technology approach based upon ruthenium redox-mediated electrochemical detection (Figure 2.14). MSD is a joint venture of its parent company, MesoScale, and IGEN, a company that pioneered much of fhe work on electrochemical detechon based on the ruthenium redox system. MSD s Multi-Spot plates contain antibodies immobilized on multiple working electrode pads within each well, allowing each spot within the well to serve as an individual assay. Multiplexed cytokine immxmoassays can be performed in 96-well (4,7, or 10 spots per well) patterns with detection limits of 1 to 10 pg/mL and a linear dynamic range up to 3,000 pg/mL. Both 24-and 384-well electrode systems are available. 

Aqueous Electrodeposition. The theory of electro deposition is weU known (see Electroplating). Of the numerous metals used in electro deposition, only 10 have been reduced to large-scale commercial practice. The most commonly plated metals are chromium, nickel, copper, zinc, rhodium, silver, cadmium, tin, and gold, foHowed by the less frequendy plated metals iron, cesium, platinum, and palladium, and the infrequendy plated metals iridium, ruthenium, and rhenium. Of these, only platinum, rhodium, indium, and rhenium are refractory. 

Ruthenocene [bis-(cyclopentadienyl)ruthenium] [I287-I3-4] M 231.2, m 195.5 , 199-210 . Sublime in high vacuum at 120 . Yellow crystals which can be recrystallised from CCI4 as transparent plates. (7ACS74 6146 1952]. 

Electronic Applications. The PGMs have a number of important and diverse applications in the electronics industry (30). The most widely used are palladium and ruthenium. Palladium or palladium—silver thick-film pastes are used in multilayer ceramic capacitors and conductor inks for hybrid integrated circuits (qv). In multilayer ceramic capacitors, the termination electrodes are silver or a silver-rich Pd—Ag alloy. The internal electrodes use a palladium-rich Pd—Ag alloy. Palladium salts are increasingly used to plate edge connectors and lead frames of semiconductors (qv), as a cost-effective alternative to gold. In 1994, 45% of total ruthenium demand was for use in ruthenium oxide resistor pastes (see ELECTRICAL CONNECTORS). 

The electrolytic cells shown in Figures 2—7 represent both monopolar and bipolar types. The Chemetics chlorate cell (Fig. 2) contains bipolar anode/cathode assemblies. The cathodes are Stahrmet, a registered trademark of Chemetics International Co., and the anodes are titanium [7440-32-6]y Ti, coated either with ruthenium dioxide [12036-10-1]y Ru02, or platinum [7440-06-4], Pt—iridium [7439-88-5]y Ir (see Metal anodes). Anodes and cathodes are joined to carrier plates of explosion-bonded titanium and Stahrmet, respectively. Several individual cells electrically connected in series are associated with... 

Other metals, such as copper, nickel, or silver, have been used as electrode materials in connection with specific applications, such as the detection of amino acids or carbohydrates in alkaline media (copper and nickel) and cyanide or sulfur compounds (silver). Unlike platinum or gold electrodes, these electrodes offer a stable response for carbohydrates at constant potentials, through the formation of high-valence oxyhydroxide species formed in situ on the surface and believed to act as redox mediators (40,41). Bismuth film electrodes (preplated or in situ plated ones) have been shown to be an attractive alternative to mercury films used for stripping voltammetry of trace metals (42,43). Alloy electrodes (e.g., platinum-ruthenium, nickel-titanium) are also being used for addressing adsorption or corrosion effects of one of their components. The bifunctional catalytic mechanism of alloy electrodes (such as Pt-Ru or Pt-Sn ones) has been particularly useful for fuel cell applications (44). 

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