In this thesis, I detail my efforts to explore organic and perovskite photovoltaic devices.
Chapter 1 introduces organic photovoltaics (OPVs) and hybrid organic inorganic perovskites (HOIPs). The central challenges of working with both organic and inorganic semiconductors are discussed. Key milestones in the development of both types of devices are highlighted and the basic operating principles of general solar cells and the distinguishing features of OPVs are addressed.
Chapter 2 gives a basic overview of preparing and testing OPVs and reflects on how the available systems and resources dictated how the projects described in Chapters 3 and 4 were designed and conducted. The remainder of the chapter provides an indepth description of several protocols developed to significantly improve the throughput of device testing in our lab and outlines in great detail the exact procedures used to prepare baseline perovskite devices with respectable efficiency.
Chapter 3 examines the importance of bulk heterojunction morphology through the addition of insulating commodity polymers. It establishes the tolerance limits of different classes of OPVs, specifically those based on small molecule and polymer donors respectively. This study was conducted in collaboration with DuPont Canada.
Chapter 4 describes my work on a series of chalcogenophene homopolymers. The study investigates how single atom substitution in conjugated polymers can be used to selectively modify properties and for the first time presents a comprehensive comparison of poly(3-alkylthiophenes), selenophenes and tellurophenes.
Chapter 5 describes the development of a solution screening assay for rapidly assessing the potential utility and necessary deposition conditions of a large number of solvents for use as antisolvents in "one-step" processing of the triple-cation perovskite reported in Chapter 2. By combining solution assay results with antisolvent physical properties and diagnostic films cast on glass the selection is refined and 15 candidates are chosen for use in solar cells. Of these, six previously unreported candidates are identified and demonstrated to have promising performance in unoptimized preliminary devices.
Chapter 6 summarizes the other chapters and outlines several project extensions and concepts.Ph.D
