PEDOT:PSS (Clevios PH1000, H. C. Starck, Goslar, Germany), PCDTBT (1-Material, Quebec, Canada), and (American Dye Source, Quebec, Canada) are used without further purification. PEDOT:PSS aqueous solution (Clevios PH1000) was used as a host polymer. The solvent additive treatment was performed by 2, 4, and 6 vol. % of and HFIPA were added into PEDOT:PSS as additives. The solution mixture was stirred vigorously for 5 h, after which it was filtered using a 0.25-μm filter. The filtered PEDOT:PSS was then deposited by spin coating at 5000 rpm for 30 s on glass and ITO coated substrates, which were precleaned with detergent, pure water, ethanol, and methanol in ultrasonication. Pristine and additive-mixed PEDOT:PSS films were annealed at 140°C for 20 min in vacuum in order to remove the water. The electrical conductivities and the thicknesses of the films were measured using Vander Pauw four-point probe method with a Keithley 2400 sourcemeter and a Dektak II surface profilometer, respectively. Optical transmittance spectra of the films were recorded using a Shimadzu UV-2450 spectrometer. Micro-Raman scattering measurements were performed in the backscattering geometry using a Renishaw in Via Raman spectrometer (532 nm). AFM images were recorded with Seiko Instruments SPA 400-SPI 4000 operating under ambient conditions in dynamic force mode. Solar cells were fabricated using an active layer of PCDTBT and (having %) in chlorobenzene by spin coating at 1000 rpm for 60 s. Then the film was dried at room temperature for 1 h and had a thickness around . Finally, a 100-nm-thick Al layer was thermally deposited in a high vacuum of . The active area of each device was . The current-voltage characteristics of the fabricated PSC devices were measured by employing an Advantest R-6441 A.C. source meter and a 100 mW solar simulator (Newport Oriel, California) with a filter having an air mass of 1.5 G (AM 1.5 G). The contact angle was analyzed with an Excimer Inc., (Kanagawa, Japan) contact angle meter. Figures 1(a)–1(c) show the molecular structure of PEDOT:PSS, HFA, and HFIPA, the energy level diagram of the active layer, PEDOT;PSS, ITO, and Al electrode and schematic diagram of fabricated PSC structure ().