4.3. Scanning Electron Microscope (SEM) and Energy Dispersive x-ray (EDAX) Analysis

EM2 and EM2 + ZnCl₂ 5% microparticles were used for investigation of ultrastructural details regarding the morphology of microparticles surface and its composition, using scanning electron microscopy with energy dispersive X-ray analysis detection (SEM-EDAX). In order to obtain an efficient EM2 + ZnCl₂ 5% mixture, in a mass ratio of 1:5, the solid compounds were dissolved in a hydro-alcoholic solution, which was sonnicated for 5 min. The solution obtained was then centrifuged at 21,000× g at 4 °C for 20 min. The pellet was dehydrated in an oven at 70 °C for 1 h and then the mixture was analyzed by SEM-EDAX. The equipment used for this analysis was an EDAX detector (ZAF Quantification – Standardless, Element Normalized) with an FEI Quanta 250 microscope. The microscope parameters were HV mode, 30kV, ETD (Everhart-Thornley detector for secondary electrons), and two magnification orders; one for a general overview image/measurements and another for higher surface topography sides analysis. The composition of microparticles was expressed in weight percent (Wt %) and atomic percent (At %).