2.4.1. Scanning Electron Microscopy (SEM)

The surface morphology of the RCMs and RPMs was determined by SEM analysis (SEM, Supra 55 Sapphire, Carl Zeiss Germany, Oberkochen, Germany). The samples were evenly coated on the conductive adhesive of the sample sheet and then sprayed with gold for 0.5 h. The surface morphology of the RCMs and RPMs after the samples were sprayed with gold was observed by SEM under low vacuum conditions.
