4.1 Materials and Solution Preparation
PBDB-TF, and ITIC-4F, were purchased from 1-Material. PC61BM was purchased from Nano-C. The PEDOT:PSS was purchased from H.C. Starck Clevios. PFN-Br was purchased from Solarmar Inc. Zinc acetate dihydrate (Zn(CH3COO)2•2H2O, 99.9%), ethanolamine (NH2CH2CH2OH, 99.5%) and 2-methoxyethanol (CH3OCH2CH2OH, >99.8%) were purchased from Sigma Aldrich. All the materials and solvents were commercially available and used without further purification. PBDB-TF and ITIC-4F were dissolved (1:1, wt%) in a mixed solution of chlorobenzene and 1,8-diiodooctane (99.5:0.5, vol%).