fig4

Figure 4. Cross-sectional (left) and top-view (right) SEM images of (A) porous H5500 membrane; (B) H0055 membrane; and (C) H3520 membrane. And top-view SEM images of the (D) H2020; (E) H2520; (F) H3020; and (G) H3520 membranes. SEM: Scanning electron microscopy.