Fig. 8 shows the appearance and SEM morphology of the fabricated paraffin/EVM-800 composite PCM.
It can be seen from Fig. 8(a) that the paraffin impregnation causes trivial appearance modification on EVM-800 (see Fig. 5(a)).
Both EVM-800 and the composite PCM share almost the same golden-yellow accordionlike appearance.
However, as demonstrated in Fig. 5(f) and Fig. 8 (b), they differ a lot in their micro-structures.
It can be seen that the EVM-800’s empty interlayer spaces are now largely occupied by the impregnated paraffin, a fact that is verified by the EDS result in Fig. 8(c).
This clearly suggests that the composite PCM can be satisfactorily fabricated by the used vacuum impregnation method, as schematically shown in Fig. 2.