*3.2.3 TEM*

**Figure 7** shows the transmission electron microscope images from NaZSM-5 h to Co/NaZSM-5 h. It can be seen that the surface of NaZSM-5 consists of pores (lighter spots) that is in accordance with the rough morphology on the crystal surface observed by SEM. After being modified by cobalt oxide in Co/NaZSM-5 h, some area on the surface of the crystal became darker. This is indicative of the dispersion

**Figure 7.** *TEM images of (a) NaZSM-5 h and (b) Co/NaZSM5-h.*

of Co species into the pores on the surface and not creating a pool or island of cobalt oxide on the surface. This also supports the results on BET measurement that cobalt oxide prefers to reside in the mesopore.
