Vapor phase electrocatalytic

M. Stoukides, and C.G. Vayenas, Transient and steady-state vapor phase electrocatalytic ethylene epoxidation, ACS Symposium Series 178 ("Catalysis under transient conditions") A.T. Bell and L.L. Hegedus, Eds., pp. 181-202 (1982). 

Transient and Steady-State Vapor Phase Electrocatalytic Ethylene Epoxidation... 

Surface — In physics and chemistry, the term surface means the termination of a solid or liquid phase bordering to vacuum. As this is an almost impossible to realize case (at least the equilibrium vapor phase of the liquid or solid phase will always boarder to the condensed phase), surface means practically always the interface between two phases, i.e., two solid phases, two liquid phases, a solid phase and a liquid phase, a solid phase and a gas phase, or a liquid phase and a gas phase. Hence, the term interface should be preferred. Since - electrodes are a major field of research in - electrochemistry (interfacial electrochemistry) the study of surfaces (interfaces) with respect to their structure, effects on -> electron transfer and - ion transfer reactions, its changes in electrochemical reactions, its - electrocatalytic effects, etc. are of major importance. 

In general, both the vapor phase as well as the aqueous phase reaction pathways indicate that C H bond activation is preferred over O H activation for most of the surface intermediates. The crossover to O H activation appears to require the activation of some of the C-H bonds first. This case study demonstrates the strong influence of the aqueous phase on determining both the fundamental pathway and energetics of electrocatalytic processes. 

In this chapter we extend our treatment of mechanisms for metal-catalyzed reactions in the vapor phase to heterogeneous catalytic reactions carried out in aqueous media and electrocatalytic reactions. More specifically, we discuss what is known about the wa-ter/metal interface, its reactivity, and the influence of the aqueous phase on elementary surface processes including adsorption, reaction, diffusion and desorption and sofution-phase kinetic processes. We advance these ideas into the discussion of the mechanisms... 

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