Fig. 3 BET-BJH analysis curve of PILs-XSS
3.1.3 SEM and EDS analysis
The structural characteristics and the surface morphology of the samples were observed by SEM. The spherical PILs-XSS was ground for SEM analysis, as shown in Figure 4, which shows the SEM picture of the sample. We can see that PILs-XSS has a fluffy pore-like structure, which is consistent with the high surface area (71.5m2/g) and the mesoporous material (14.8nm), which well explains the special advantages of the catalyst PILs-XSS in the reaction[32].
The samples were characterized and analyzed by EDS to study their composition, distribution. The EDS analysis of the samples is shown in Table 1. It can be seen from the table 1 that bromine was detected in the catalyst PILs-XSS, which is important for the addition reaction of CO2 and propylene oxide. For EDS detection, the results are similar to the theoretical ratio. It was further proved that PILs-XSS was synthesized successfully.
Table 1 EDS analysis of PILs-XSS