The Polymer Society of Korea

Abstract

Precise control of molecular electronic structures and molecular packing is critical for organic energy harvesting devices. Here, we present molecular engineering strategies based on backbone and side-chain design of conjugated polymers and nonfullerene acceptors (NFAs) to achieve tunable electronic structures and improved device characteristics. Side-chain engineering of NFAs modulates intermolecular interactions, molecular orientation, and thin-film morphology, enabling controlled charge transport and enhanced photovoltaic performance, reproducibility, and thermal stability in organic solar cells. In parallel, wide-bandgap conjugated copolymers and terpolymers are designed to control backbone planarity, energy-level alignment, and carrier transport. Comparative studies on backbone isomerization and terpolymerization highlight their roles in balancing photovoltaic and thermoelectric performance, demonstrating the versatility of molecular design for energy harvesting applications.