Investigating the effects of solvents on the performance of poly(3-hexylthiophene-2,5-diy1) (P3HT):C61-butyric acid
methyl ester (PCBM) bulk heterojunction solar cells, we found the short current density (Jsc), fill factor(FF),and power
conversion efficiency (η) of a cell with a photo-active layer made using materials dissolved in a higher boiling point
solvent to be higher than those of a cell made using the same materials dissolved in a low boiling point solvent.
Evaluating the surface morphology, charge mobility, and current-voltage curve of cells made using different solvents, we
concluded that the polymer films using a higher boiling point solvent had longtime to self-organize, got a higher degree
of crystalline, led to lower device series resistance, thereby increased the short current density (Jsc), fill factor(FF),and
power conversion efficiency (η) of the photovoltaic devices.