fig4
Figure 4. HRTEM images of (A), (D) PBED, (B), (E) P(BED-T) and (C), (F) P(BED-TT) films.BED-T: 2,5-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)thiophene; BED-TT: 2,5-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)thieno[3,2-b]thiophene; HRTEM:confirmed by high resolution transmission electron microscopy.