Curt Zimmermann

Ultrahigh vacuum compatible all-glass high pressure reaction cell for accurate and reproducible measurement of small reaction rates

An ultrahigh vacuum preparation and analysis chamber with an externally attached high pressure reaction cell is described. The novel all-glass design of the reaction cell allows the study of reaction kinetics in a clean environment but under conditions close to those of conventional catalysis. Reactions on supported metals can be studied on pairs of “real” and “inverse” type model catalysts in the same experimental system under identical sample geometry. No supports or wires are connected to the catalyst while in the high pressure cell, and background activity can therefore be excluded. The experimental setup described required the construction of a special transfer mechanism for in situ manipulation of the samples. As a test reaction, CO hydrogenation has been studied on a transition metal oxide modified rhodium metal surface, and some initial results are presented.