The objective of this research is to develop improved materials and advance fundamental understanding of properties that are needed for enhanced performance of organic semiconductors in solar cells and relevant diodes. The approach combines synthesis of new semiconductor materials with a set of physical characterization methods that enable detailed probing of the interfaces between materials that control device performance.
Intellectual merit: In order to realize applications of organic devices, improved understanding of charge transport through organic materials and across their junctions is needed. This project includes synthesis and exploration of new materials combinations, focusing on morphological, interfacial, photophysical, and charge transport properties. Rigorous characterization techniques, including nanoscale scanning and photosensitive Kelvin probes, neutron scattering and depth profiling that have not often been brought to bear on these devices will be employed. Scanning gate microscopy will be introduced for pn junction characterization. New insight into the smoothness, voltage steps, and interfacial conductivities at junctions that are formed below the surface, or in the bulk, of device films will be gained, and used to enhance performance parameters of organic devices.
Broader impacts: The increased understanding of material and device properties that will result from this work will enable the synthesis of new materials with improved performance in solar cell applications. The project will provide multidisciplinary research training for graduate students in science and engineering, including members of underrepresented groups through collaborations with Howard University. The results of this work will be used to enhance both undergraduate and high school science education.