Figure 5: Vertical morphologies of blended films.

(a) Surface enrichments of BTID-0F/PC₇₁BM, BTID-1F/PC₇₁BM and BTID-2F/PC₇₁BM on ZnO/ITO substrate; (b) in-depth XPS profiles of BTID-0F/PC₇₁BM and BTID-2F/PC₇₁BM on ZnO/ITO substrates, the line were obtained from fitting all the S:C value from various etching time; (c) carrier mobilities of blends and pristine films, the average values were obtained from the mobility measured from the thickness between 100 and 130 nm, the error bars come from the mobility value from thickness differences and their measurements errors; and (d) schematic illustrations of lateral and vertical phase distribution of BTID-2F/PC₇₁BM.