NSF Award
2414281
The research project aims to advance organic solar cells (OSCs) to support the shift from non-sustainable to sustainable energy sources. While OSCs have achieved significant power conversion efficiency, their large-scale production faces challenges due to the use of toxic solvents that are harmful to both the environment and public health. This project will develop greener manufacturing processes using eco-friendly, biomass-derived solvents such as Cyrene and γ-valerolactone (GVL). These bio-based solvents offer reduced toxicity compared to the currently used solvents. One challenge is that the current components for OSCs are not compatible for processing with these two greener solvents. This project will use an innovative combination of experiments and molecular simulation to rationalize the design of new chemical functionalities with characteristics to improve their solubility. This collaborative project will provide outstanding opportunities for training graduate students in interdisciplinary approaches that integrate experiments and simulations. The project will also support educational opportunities and promote diversity in STEM by participating in local outreach activities such as the "Harvesting Sun Light" workshop for the Expanding Your Horizons conference, designed to inspire middle school girls to engage with STEM. <br/><br/>The primary objective of this project is to design and synthesize zwitterlated conjugated polymers and organic molecules that can be processed using the biomass-derived solvents Cyrene and GVL. The researchers hypothesize that tuning the charged group pairs in zwitterionic sidechains will control the solubility and assembly of these materials in the selected solvents. The research approach combines computational and experimental research: molecular simulations will explore the thermodynamics of solvation and assembly of the polymers and molecules in Cyrene and GVL, while experimental efforts will focus on synthesizing these zwitterlated materials and characterizing their assembly and film morphology. The researchers aim to develop manufacturing processes that produce high-performance OSCs with power conversion efficiencies exceeding 15%. This research will advance understanding of the role of zwitterionic sidechains in solubility and assembly, illustrate their impact during the nonequilibrium solvent evaporation process, and result in the development of multiple high-performance zwitterlated polymer systems and manufacturing processes. The outcome of this collaborative project will be the molecular principles for designing zwitterlated polymers and molecules that can be used to produce high-performance OSCs using Cyrene and GVL-based processes and several such polymers and molecules.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
