Evaporated organic photovoltaics with microstructural tuning using Self-Assembled Monolayers

This proposal seeks to use grazing incidence wide angle X-ray scattering (GIWAXS) to characterise the microstructure of vacuum thermally evaporated (VTE) organic photovoltaics (OPV), tuned with templating layers. Improved power conversion efficiency of OPV has resulted in part from optimized processing protocols - influencing changes in microstructure, governing device performance. In the context of quantities probed via GIWAXS; molecular orientation plays a significant role in light absorption and molecular ordering affects charge carrier transport and recombination. Templating layers can induce a different crystalline polymorph and preferred molecule orientation in overlayers. A class of materials already successfully implemented in solution processed OPV as both a charge transport layer and a morphological template is self-assembled monolayers (SAMs). This proposal aims to investigate SAMs in a VTE OPV context, quantifying the molecular changes that the SAM induces.