Surface areas ruthenium blacks

It was seen when studying mixed systems Pt-WOj/C and Pt-Ti02/C that with increasing percentage of oxide in the substrate mix the working surface area of the platinum crystallites increases, and the catalytic activity for methanol oxidation increases accordingly. With a support of molybdenum oxide on carbon black, the activity of supported platinum catalyst for methanol oxidation comes close to that of the mixed platinum-ruthenium catalyst. 

The surface areas of a number of commercial palladium blacks were measured using the BET procedure as well as hydrogen chemisorption, electron microscopy and X-ray diffraction analysis. These data showed that these blacks had particle sizes ranging from about 7 to 140 nm and surface areas between 70 and 4 m2/g.20 Ruthenium blacks prepared by the reduction of different samples of ruthenium oxide and ruthenium chloride were found to have surface areas ranging from 3-20 m2/g.21... 

In a more recent study, Li et al. [15] investigated the catalytic behavior of ruthenium catalysts supported on carbon materials with different porous and graphitic structures in the catalytic ammonia decomposition. They found that the catalytic activity followed the trend Ru/GC (graphitic carbon)> Ru/CNTs (carbon nantoubes) > Ru/CB-S (carbon black) > Ru/CB-C > Ru/CMK-3 (meso-porous carbon) = Ru/AC. It was concluded that the graphitic structure of the carbons was critical to the activity of the ruthenium catalysts, whereas the surface area and porosity were less important. 

Another approach that minimizes Ru content is to combine large surface area materials with RuOg. Supercapacitors based on activated carbon and ruthenium oxides were developed by Zheng et al. in 1996 [65] and recently optimized [66]. They demonstrated that the addition of carbon black with a high surface area (1300 m -g" ) increases electrode porosity, a benefit for the proton transfer within the electrode. In addition. 

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