“…The modifications of the PGEs either in the final form or during the intermediate steps involving the deposition of various materials [53,60,69,85,86,127,130,131,143] must be proven by surface analysis using non-destructive techniques like scanning electron microscopy (SEM) [41,46,52,60,67,87,88,106,119,124,127,133,[144][145][146]151], field effect SEM (FE-SEM) [108,110,128,134,142,150], transmission electron microscopy (TEM) [52,87,134,144,146], and atomic force microscopy (AFM) [36,37,109,110]. These techniques, either alone or in combination, give valuable information about the surface morphology (e.g., texture and distribution of the materials [50,62,65,72,90,…”