A transition solvent strategy to print polymer:fullerene films using halogen-free solvents for solar cell applications

摘要: Abstract Inkjet printing is a mask-less non-contact deposition technique that potentially suited for prototyping and manufacturing of thin-film polymer organic semiconductor devices from digital images. However new strategies are needed to achieve films with good macromorphology (i.e., high-fidelity footprint uniform cross-section) nanomorphology on unstructured substrates using conventional ink-jet. Here we report transition solvent strategy provide the desired film ultrafine in regioregular poly(3-hexylthiophene):phenyl-C 61 -butyric acid methyl ester (P3HT:PCBM) model films, without chlorinated solvents. This employs volatile combination miscible poor much less volatile, which reverse usual low−high boiling-point method. The suppresses premature aggregation ink head. Its removal by evaporation substrate leaves triggers early π-stacking ordering and/or gelation matrix immobilizes printed fluid substrate, suppressing both contact-line depinning evaporation-induced flow effects. resultant donor–acceptor further improved vacuum drying at an optimal rate avoids bubble formation. We have systematically characterized P3HT:PCBM deposited different solvents platen temperatures identify key macro- nano-morphology determining processes. High-performance solar cells were realized. These findings applicable also other coating techniques based low-viscosity inks.