Nucleobase Polymers Promote Low Work Function Surfaces in Organic Electronics

Abstract

Low work function surfaces are crucial to electron extraction and injection in organic electronic devices. One of the challenges is developing general surface modifiers compatible with various organic semiconductors and device structures. Two novel nucleobase polymers are synthesized by reversible addition-fragmentation chain transfer polymerization. The nucleobase polymers show strong molecular dipole moments and superior film-forming property as surface modifiers, which universally reduce work functions of common conductive electrodes. The integration of these nucleobase polymers into conventional or inverted organic solar cells (OSCs) boosts efficiencies of the devices to 17.25%, which is the highest in OSCs containing biomass-derived interlayer materials. These nucleobase polymers are efficient and stable surface modifiers to remove energy barriers of diodes and transistors, improving electron transport between metal electrodes and organic semiconductors, which provide a new material platform for introducing biomass-derivatives to produce low work function surfaces for high-performance organic electronics.