الفهرس 
list of abbreviations and symbolsOnly 14 pages are availabe for public view
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Abstract
In this study a blend of P3HT: PCBM of constant weight ratio 1:1 was used for OPV BHJ cell fabrication. The effects of two host solvents (CB and oDCB) were studied on the film morphology by scanning electron microscope. Films casted from oDCBhost solvent blend show relatively larger P3HT crystallization due to the lower solvent evaporation rate (higher boiling point). The effects of different solution concentrations (30 mg/ml and 34 mg/ml) on OPV cell performance were investigated. The cell fabricated by 34mg/ml solution concentration showed a higher performance. Different preparation techniques were used in order to obtain further P3HT: PCBM thin film morphology control and the resultant samples were investigated by SEM, UV-Visible spectroscopy and XRD. SEM images of solvent annealed active layer reveal the good blend dispersion. Further study of thin film morphology control was carried out using mixed solvents by applying 1:1 weight ratio of CB: oDCB and oDCB: TCB solutions. Thermal annealing with different annealing temperatures (100°C and 120°C for 5 minutes) was found to affect the thin film morphology and the cell performance as well. Thermal annealing at 120°C showed better OPV cell performance due to well ordering of film components and getting rid of residual solvents efficiently. The best cell Jsc 3.5 mA/cm2 was obtained by using 1:1 ratio of CB: oDCB mixed solvents and thermal annealing and the active layer was allowed to be solvent annealed for 20 minutes. The LiF thin film insertion as a hole blocking layer was found to increase Voc.
P3HT nanofibers was prepared by using solution ageing technique. Ageing of P3HT solution in P-Xylene produces P3HT nanofiber for more than three days. Nano fibers were characterized by UV- Visible absorption spectroscopy and TEM. In addition, TiOx was prepared by sol-gel technique.