Sunny With a Chance of Power: Adding Interstitial Layers to Improve Open-Circuit Voltage in Organic Solar Cells
As carbon dioxide levels rise and oil reserves run low, there is a growing need for alternative fuel sources. Harvesting the sun’s abundant energy through photoconversion offers a viable, long-term solution for a sustainable future. Unlike conventional silicon solar cells, organic photovoltaics (OPVs) – solar cells consisting of organic materials – are inexpensive, easy to produce, lightweight and flexible. However, low power conversion efficiencies due to limited open-circuit voltage (Voc), prevent them from competing with silicon cells commercially. This summer I worked at the Arango Lab at Mount Holyoke College to investigate the effects of adding interstitial layers to planar OPVs. The planar cells comprise of a spin-cast conjugated polymer electron donor and a fullerene derivative acceptor layer deposited via transfer printing. We hope to maximize the donor-acceptor interface by sandwiching wide-bandgap organic films between the donor and acceptor layers. This talk focuses on how the increase in interfacial bandgap can result in improved device performance, and eventually help provide low-cost energy from the sun using OPVs.