(284f) Understanding Film-to-Wire Transition of Conjugated Polymers Driven By Meniscus Instability
AIChE Annual Meeting
Tuesday, October 30, 2018 - 9:15am to 9:30am
In this work, we observed coating speed dependent film-to-nanowire morphology transition driven by stick-and-slip meniscus instability across multiple high-performance donor-acceptor conjugated polymer systems. Interestingly, the nanowires exhibit different molecular stacking and higher charge carrier mobility compared to thin films deposited at the same condition. We hypothesize that the film-to-wire morphology transition is determined by minimization of the meniscus surface free energy during the stick-and-slip meniscus motion. We validated the hypothesis by constructing a quantitative surface free energy model and successfully showed the peak of meniscus surface free energy occurring at the transition coating speed. This work is a significant first step towards quantitative understanding of meniscus-instability-driven morphology transition during solution coating, which represents a promising approach for lithography-free patterning. Our study has broad implications beyond printed electronics, given the critical importance of controlling meniscus instability and deposit morphology in a wide range of scientific disciplines and technology sectors.