Electron microscopy, gold decoration

Developments in electron microscopy also promise to revolutionize other studies of the surfaces of solids in general and/of catalysts in particular. Previously, monatomic steps and other topographical features at the exterior surfaces of solids were best investigated by the powerful but cumbersome, and destructive technique of gold-decoration - see refs 69 and 70 for studies of alkali halide and layered sulphides, respectively. 

An even more refined method of study is interference-contrast microscopy [following Nomarski (767)] which converts minute topographical differences into color changes. Replica electron microscopy (77), gold decoration (see Section III,A,1), and scanning electron microscopy are also useful but less practicable. Occasionally it is profitable to follow the course of the reaction, in situ, using time-lapse cinematography (77). 

The surface topography of the partially oxidized specimens is examined, with low resolution, using interference-contrast microscopy and at high resolution by means of the gold-decoration technique 177, 180) in conjunction with transmission electron microscopy. 

Scanning electron microscopy (SEM) examinations, [29] of the macroscopic morphology of dissolution were then substantiated by transmission electron microscopy (TEM) pictures of gold-decorated surfaces [30]. The better resolution, even though not truly atomic, allowed an estimate of x and Xj and of their dependence on the dissolution rate as shown in Figure 4. The surface concentration of kinks (XjX ) is an exponential function of the potential with an exp(F /i 7)... 

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