In this talk, I will discuss recent progress at UCSB on the development of donor and acceptor materials for application in solution processed bulk heterojunction solar cells. Chemical structure and processing conditions can be used to tune the energy level, bandgap, solubility, molecular packing, film morphology, charge generation, charge mobility, charge recombination, and therefore, the device performance. A combination of techniques is employed to characterize material properties especially film morphology including steady-state and time-resolved spectroscopy, atomic force microscopy (AFM), photoconductive AFM, TEM, GIWAXS, and impedance spectroscopy. The results from these studies provide design guidelines for new generation of materials for applications in organic solar cells.
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