EFFECT OF INTERACTIONS AMONG METAL, SUPPORT AND ATMOSPHERE ON THE BEHAVIOUR OF SUPPORTED METAL CATALYSTS.

Abstract

The paper is mainly concerned with wetting and spreading in catalyst-substrate systems and with the roles played by the interactions among catalyst, atmosphere and substrate in the above phenomena. First, the thermodynamics of spreading is analyzed followed by an explanation of the higher mobility of the catalyst atoms on the surface of the crystallites above the Tamurann temperature. Experimental results are presented which provide evidence for the extension of the crystallites during heating in O//2 followed by contraction during subsequent heating in H//2, as well as on their splitting and change in shape.