Global energy use relies heavily on fossil fuels and the related emissions are one of the largest contributors to climate change. Consequently, the demand for solar energy, a clean and sustainable energy source, is only increasing. Solar cell devices using organic photovoltaic materials (OPVs) are being widely studied as cost-effective and sustainable alternatives to fossil fuels. The objective of our project is to synthesize new conjugated organic polymers using greener synthetic methods for use in new solar cell materials. Conjugated organic polymer properties are highly tunable and can be manipulated to achieve high power conversion efficiencies in OPV devices. We chose to synthesize monomers (small molecules used as building blocks to make polymers) with high solubility and a rigid planar backbone to engineer desirable optical properties in our goal polymer. We successfully synthesized our novel goal monomer in high yield using a two-step reaction scheme and only a single purification step. In order to verify the structure and purity of the synthesized monomer, we utilized numerous techniques including nuclear magnetic resonance and mass spectroscopy. Using the green method of direct arylation polymerization, we synthesized our desired goal polymer from our new monomer. This method of direct arylation bypasses typical polymerization reactions involving toxic reagents and hazardous procedures. Preliminary optical measurements provide evidence that our new polymer has favorable properties for use in OPV devices including efficient low energy light absorption. The short synthetic pathway, high yield reactions, and green synthesis of this polymer make this attractive to commercial OPV application.
Green Synthesis of Conducting Polymers for Organic Photovoltaic Applications
Category
Chemistry