*3.5. Scanning Electron Microscopy*

SEM imaging was conducted to provide insight on the morphology of the samples obtained before and after ageing and is depicted in Figure 14. Prior to ageing, both S1 and S2 depicted similar morphology with no obvious differences observed. Ageing of the samples resulted in the formation of thin platelet like structures. These were observed to correlate with SEM images associated with Mg-Al LDH reported in literature [9]. No obvious morphological di fferences were observed between S3 and S4 prior to ageing. Ageing of S3 resulted in the formation of thin crystalline platelets which correlate to those reported in literature for Ca-Al LDH1. Comparatively, S4 depicted structures associated with katoite, calcite, and Ca-Al LDH, and was observed to coincide with the XRD data obtained. No clear morphological di fferences were observed for S5 and S6 before and after ageing. Platelet like structures could be construed as being present.

**Figure 14.** *Cont.*

**Figure 14.** SEM imaging of samples before and after ageing. Imaging was conducted at a magnification of 50.00 K with a 200 nm scale and EHT of 1.00 kV for all samples. Additional imaging was conducted for S3aged at a scale of 10 μm, EHT of 20.00 kV and magnification of 4.00 K. Similarly S4aged was imaged with a scale of 1.00 μm, EHT 1.00 kV and magnification of 15.00 K.
