Figure 2

SEM images of as-prepared p-PBIPE membranes. Surfaces: (a) wp-PBIPE, (b) ep-PBIPE, (c) ap-PBIPE, and (d) cp-PBIPE; cross-section: (a’) wp-PBIPE, (b’) ep-PBIPE, (c’) ap-PBIPE, and (d’) cp-PBIPE.

SEM images of as-prepared p-PBIPE membranes. Surfaces: (a) wp-PBIPE, (b) ep-PBIPE, (c) ap-PBIPE, and (d) cp-PBIPE; cross-section: (a’) wp-PBIPE, (b’) ep-PBIPE, (c’) ap-PBIPE, and (d’) cp-PBIPE.