Pc71bm

Donor polymer PM6 (M_n: 24.2 kDa; M_w: 88.0 kDa; PDI: 3.361) was provided by Solarmer Materials Inc. PC₇₁BM was purchased from Sigma-Aldrich. N3 and Y6-O were synthesized according to the procedures in the literatures^{27 (link),58 (link)}.

We fabricated BHJ type OSCs with a ternary AL that consisted of PM6 (1-Material), Y6 (1-Material), and PC₇₁BM (Sigma Aldrich) on an ITO-coated (10 Ω sq⁻¹) glass substrates based on an inverted device architecture of ITO/ZnO/AL/MoO₃/Ag. ITO-cathode and Ag-anode patterns defined the square solar-cell area of 0.4 × 0.4 cm². ZnO and MoO₃ were electron- (EELs) and hole-extraction layers (HELs), respectively. Device fabrication started by thoroughly cleaning ITO surfaces according to a conventional recipe. Just prior to spin-coating a dispersion solution of 12-nm ZnO nanoparticles in IPA (Avantama), we treated ITO surfaces with oxygen plasma. ZnO EELs with a thickness of 40 nm were formed following a post annealing step at 80 ˚C for 10 min. We formed ALs similarly by combining spin-coating and post-annealing steps. The precursor solution for ALs was prepared by dissolving 7 mg of PM6, 7 mg of Y6, and 1.4 mg of PC₇₁BM in 1 ml of chloroform, and then adding 0.5 V% of chloronaphthalene to the mixture solution. Post-annealing for 10 min at 90 ˚C completed the formation of 90-nm thick ALs. Finally, we deposited a 10-nm thick MoO₃ HEL and a 100-nm thick silver anode in succession using a thermal evaporator equipped with a thickness monitor. We protected fabricated OSCs against exposure to ambient air using epoxy-glass encapsulation.

F₂-TES ADT was synthesized as described previously68 (link). PC₇₁BM, tetracene, rubrene, TIPS-pentacene and pentacene were purchased from Sigma Aldrich. F₂-TES ADT and TIPS-pentacene thin film samples were spin-cast (15 mg ml⁻¹, toluene) on polyimide precoated fused-silica substrates (the polyimide aids wetting of the organic semiconductor). For F₂-TES ADT: PC₇₁BM thin film samples, 4:1F₂-TES ADT:PC₇₁BM blend solutions (15 mg ml⁻¹ total material, mesitylene) were spin-cast on polyimide precoated fused-silica substrates. Samples were dried on a hot-plate at 50 °C for 10 min. Tetracene, rubrene and pentacene thin-film samples were prepared via thermal evaporation at a base pressure of <6 × 10⁻⁶ mbar.
Single crystals of F₂-ADT were grown through a physical vapour growth method. Details of the relevant method can be seen elsewhere69 . We used a growth apparatus equipped with source and growth heaters that were placed side-by-side. Temperatures of the heaters were regulated in such a way that high-quality single crystals could be produced. In the present studies we set the source and growth heaters at 240 °C and 220 °C, respectively. The growth duration was 6 h.