Catalytic reactions on metals

NakatsujI H 1987 Dipped adcluster model for chemisorptions and catalytic reactions on metal surface J. Chem. Phys. 87 4995-5001... 

Examples of Elementary Processes in Heterogeneous Catalytic Reactions on Metal Oxides... 

In an exploratory sort of way the F.E.M. has been used to study catalytic reactions on metal surfaces. While such studies are far from complete, they clearly indicate that this new tool can reveal details of the mechanism of such reactions to a much greater extent than is possible by any other known technique. We shall here discuss only two systems H2, O2 and H2O on W and C and O2 on W. 

Dynamics of catalytic reactions on metal surfaces (with L.D. Schmidt). In Unsteady State Processes in Catalysis, (pp. 203-216). Utrecht, Holland VSP Press, 1990. 

In catalytic reactions on metals a decrease in activation energy under UV illumi-tion is also observed 97 "). In experiments on CO oxidation on evaporated Ag, Au, Pd and Pt films 98 a decrease is observed in the activation energy due to... 

V.B. Kazansky and V.V. Voevodsky, The Study of Mechanism of Catalytic Reactions on Metallic Palladium. Physics and Physical Chemistry of Catalysis. (Problems of kinetics and catalysis. V. 70), Moscow. Acad. Sci. USSR. 1960, p. 398. 

Somorjai GA, McCrea KR (2000) Sum frequency generation Surface vibrational spectroscopy studies of catalytic reactions on metal single-crystal surfaces. Adv Catal 45 385... 

F. Heterogeneous-Homogeneous Catalytic Reactions on Metal Catalysts... 

Although this research work, carried on for many years, resulted in a vast amount of valuable data, a closer study of the catalytic behavior of metallic compounds may be said to have been initiated by Schwab and Rienacker, who, from 1936 onwards, made extensive researches to investigate the decomposition of formic acid on a large variety of metals and metal alloys. These workers primarily attempted to find an answer to the question whether or not the rate of catalytic reactions on metals in general is influenced by alloying these metals with others in such a way that the electron concentration increases. 

Catalytic reactions on metal surfaces are often remarkabily influenced by foreign metals. The Pt-Rli catalyst used for automotive exliaust gas control is a typical example. The Pt-based catalyst is markedly improved by adding Rli, but the roles of Rli are still controversial. In order to tlrrow light on such fundamental problems, we studied the adsorption of NO and the reaction of NO with H2 on Pt-Rli(lOO) alloy surface [1,2,3]. 

Unexpectedly, the specific rates remain constant, i.e. they do not depend on the metal dispersion [15] for most of the reactions investigated [16]. The first exceptions observed were the isomerization and hydrocracking of neopentane on platinum [17]. For these reactions the specific rates vary with dispersion by factors of 15 and 300, respectively. This result led Boudart to classify the catalytic reactions on metals as Facile or Structure insensitive reactions, for which the specific rates do not depend upon the size of the metal particle, and Demanding or... 

Simulation of catalytic reactions on metal films allows closer spectroscopic examination of the reacting system. A more recent step from convention is the use of molecular beams. 

On the atomic level, this is clearly observed in many catalytic reactions on metal surfaces, where the crystal face of the metal concerned can greatly influence the catalyzed rate of reaction (see Chapter 3a). One of the most significant effects of... 

The interesting role which solid electrolytes can play in the study of heterogeneous catalysis was first recognized by Wagner, who proposed the use of solid electrolyte cells for the measurement of the activity of oxygen on metal and metal oxide catalysts. This technique, first used to study the mechanism of SO2 oxidation on noble metals, was subsequently called solid electrolyte potentiometiy (SEP). It has been used in conjunction with kinetic measurements to study the mechanism of several catalytic reactions on metals and, more recently, metal oxides. It is particularly suitable for the study of oscillatory catalytic reactions. - The SEP literatnre has recently been reviewed. ... 

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