Soft electronic materials, including organic and polymeric electronic materials, have gained great interests for their applications in next-generation electronic devices. This thesis presents (1) my study on charge carrier dynamics in organic solar cells and (2) my study on vapor-phase synthesis of conjugated polymers and its applications.

Chapter 2 presents the study on organic solar cells. we investigated vapor-deposited, planar heterojunction organic solar cells containing a periflanthene donor and either a fullerene or non-fullerene acceptor. A high open-circuit voltage of 1.16V is observed in devices containing the non-fullerene, pyrrolo[3,4-c]pyrrole-1,4-dione, 3,6-bis(4-chlorophenyl)-2,5- dihydro acceptor, whereas analogous devices containing C60 only result in a Voc of 0.8 V. The measured band energy levels of the two different acceptors do not readily explain the observed difference. Small-perturbation transient photovoltage and transient photocurrent measurements revealed that interfacial charge recombination is comparatively slower for the non-fullerene acceptor, resulting in relatively higher Voc values.

Chapter presents a vapor deposition chamber that, allow for in situ vapor phase polymerization of a representative selection of common conjugated monomers, some of which are first polymerized by vapor phase deposition. Conformal coating of highly disordered, high surface area three-dimensional substrates, including a cotton towel and corduroy fabric is described.

Next, Chapter 4 and 5 present the two applications of vapor-deposited polymers: functionalizing fabrics and coating nano-structured covalent organic framework (COF). Hydrophobic fabrics created using reactive vapor deposition and post-deposition functionalization are effective, reusable, large-volume oil-water separators, either under gravity filtration or as immersible absorbants. Conductive polymers can be coated uniformly and conformally on nano-structured covalent organic framework (COF) to increase its performance in energy storage devices.

Last, Chapter 6 presents the study on applying vapor-deposited conjugated polymers in organic electronics. It includes syntheses and characterizations of a library of vapor-deposited polymers, performing copolymerization in vapor phase deposition, and organic solar cells using vapor-deposited polymer as the hole transport layer.