Fig. 3

SEM images of (a) PES, (b) PES/CS-2.5%, and (c) PES/CS-5% membranes cross-section. Cross-sections of (d) PES, (e) PES/CS-2.5%, and (f) PES/CS-5% membranes at larger magnification. Top surfaces of (g) PES, (h) PES/CS-2.5%, and (i) PES/CS-5% membranes. (j) Top layer thickness of synthesized membranes. (k) FT-IR spectra of the membranes