A Study of the Relationship Between Microstructure and Photophysics in Organic Semiconductor Blends for Solar Cell Applications

This thesis is a study of material blends involving organic semiconductors and their applicationto opto-electronic devices, particularly photovoltaic diodes. Its principal aim is to examinethe microstructure of the blend, where microstructure is defined as molecular ordering andspatial arrangement on the nanometer to micrometer scale. In general, each chapter of thethesis presents a novel means by which to influence the microstructure of organic semiconductorblends. These techniques are used as a means to understand how the photophysics of optoelectronicdevices is influenced by microstructure. We establish some general principles of howmicrostructure relates to device performance and also find high performance in some entirelynovel device structures and architectures. It is hoped that understanding developed here willlead to improvements in the performance of organic photovoltaic devices.