Cooperative Surface‐Particle Catalysis: The Role of the “Active Doughnut” in Catalytic Oxidation

摘要: We consider the factors that govern activity of bifunctional catalysts comprised active particles supported on surfaces. Such are interesting because adsorption and diffusion steps, which often discounted in "conventional" catalytic scenarios, play a key role here. present an intuitive model, so-called "active doughnut" concept, defining region around particles. This simple model explains steps cascade cycles for The concept has two important practical implications. First, reaction rate is no longer proportional to number sites, but rather "communicative" sites-those available intermediates during their respective lifetimes. Second, it generates testable prediction concerning dependence total particle size. With these tools at hand, we examine six experimental examples oxidation from literature, show doughnut gives valuable insight even when detailed mechanistic information hard come by.